feat: user data purge, breadcrumbs, first-login dialog, widget consolidation, bookkeeping cascade

- Admin can purge all personal data for a user (POST /api/admin/users/:userId/purge-data)
  while keeping the account; clears profile, notifications, bookings, ical tokens, preferences
- Add isNewUser flag to auth callback response; first-login dialog prompts for Standesbuchnummer
- Add PageBreadcrumbs component and apply to 18 sub-pages across the app
- Cascade budget_typ changes from parent pot to all children recursively, converting amounts
  (detailliert→einfach: sum into budget_gesamt; einfach→detailliert: zero all for redistribution)
- Migrate NextcloudTalkWidget to use shared WidgetCard template for consistent header styling

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/src/controllers/auth.controller.ts

@@ -100,6 +100,7 @@ class AuthController {
 
       // Step 4: Find or create user in database
       let user = await userService.findByAuthentikSub(userInfo.sub);
+      const isNewUser = !user;
 
       if (!user) {
         // User doesn't exist, create new user
@@ -230,6 +231,7 @@ class AuthController {
         data: {
           accessToken,
           refreshToken,
+          isNewUser,
           user: {
             id:                user.id,
             email:             user.email,

backend/src/routes/admin.routes.ts

@@ -20,6 +20,7 @@ import { requirePermission } from '../middleware/rbac.middleware';
 import { auditExport } from '../middleware/audit.middleware';
 import auditService, { AuditAction, AuditResourceType, AuditFilters } from '../services/audit.service';
 import cleanupService from '../services/cleanup.service';
+import userService from '../services/user.service';
 import pool from '../config/database';
 import logger from '../utils/logger';
 
@@ -440,4 +441,53 @@ router.delete(
   }
 );
 
+// ---------------------------------------------------------------------------
+// POST /api/admin/users/:userId/purge-data — delete all user-associated data
+// (keeps the users record, financial records, and audit log)
+// ---------------------------------------------------------------------------
+
+router.post(
+  '/users/:userId/purge-data',
+  authenticate,
+  requirePermission('admin:write'),
+  async (req: Request, res: Response): Promise<void> => {
+    try {
+      const targetUserId = req.params.userId as string;
+      const requestingUserId = req.user!.id;
+
+      const targetUser = await userService.findById(targetUserId);
+      if (!targetUser) {
+        res.status(404).json({ success: false, message: 'Benutzer nicht gefunden' });
+        return;
+      }
+
+      const result = await userService.purgeUserData(targetUserId, requestingUserId);
+
+      // Audit log
+      await auditService.logAudit({
+        user_id: requestingUserId,
+        user_email: req.user!.email,
+        action: AuditAction.DELETE,
+        resource_type: AuditResourceType.USER,
+        resource_id: targetUserId,
+        old_value: { email: targetUser.email, name: targetUser.name },
+        new_value: { purged_tables: result },
+        ip_address: req.ip ?? null,
+        user_agent: req.headers['user-agent'] ?? null,
+        metadata: { operation: 'purge_user_data' },
+      });
+
+      res.json({ success: true, data: result });
+    } catch (error) {
+      const message = error instanceof Error ? error.message : 'Fehler beim Löschen der Benutzerdaten';
+      if (message === 'Cannot purge your own data') {
+        res.status(400).json({ success: false, message: 'Eigene Daten können nicht gelöscht werden' });
+        return;
+      }
+      logger.error('Failed to purge user data', { error, userId: req.params.userId });
+      res.status(500).json({ success: false, message: 'Fehler beim Löschen der Benutzerdaten' });
+    }
+  }
+);
+
 export default router;

backend/src/services/buchhaltung.service.ts

@@ -653,6 +653,36 @@ async function createKonto(
   }
 }
 
+async function cascadeBudgetTypToChildren(parentId: number, newType: string): Promise<void> {
+  const children = await pool.query(
+    'SELECT id, budget_typ, budget_gwg, budget_anlagen, budget_instandhaltung, budget_gesamt FROM buchhaltung_konten WHERE parent_id = $1',
+    [parentId]
+  );
+
+  for (const child of children.rows) {
+    const oldType = child.budget_typ || 'detailliert';
+    if (oldType === newType) continue;
+
+    let gwg = 0, anlagen = 0, instandhaltung = 0, gesamt = 0;
+
+    if (oldType === 'detailliert' && newType === 'einfach') {
+      // Sum detail fields into gesamt
+      gesamt = (parseFloat(child.budget_gwg) || 0) + (parseFloat(child.budget_anlagen) || 0) + (parseFloat(child.budget_instandhaltung) || 0);
+    }
+    // einfach → detailliert: zero everything (user redistributes manually)
+
+    await pool.query(
+      `UPDATE buchhaltung_konten
+       SET budget_typ = $1, budget_gwg = $2, budget_anlagen = $3, budget_instandhaltung = $4, budget_gesamt = $5
+       WHERE id = $6`,
+      [newType, gwg, anlagen, instandhaltung, gesamt, child.id]
+    );
+
+    // Recurse into grandchildren
+    await cascadeBudgetTypToChildren(child.id, newType);
+  }
+}
+
 async function updateKonto(
   id: number,
   data: { konto_typ_id?: number; kontonummer?: string; bezeichnung?: string; parent_id?: number | null; budget_gwg?: number; budget_anlagen?: number; budget_instandhaltung?: number; notizen?: string; kategorie_id?: number | null; budget_typ?: string; budget_gesamt?: number }
@@ -711,6 +741,15 @@ async function updateKonto(
       `UPDATE buchhaltung_konten SET ${fields.join(', ')} WHERE id = $${idx} RETURNING *`,
       values
     );
+
+    // Cascade budget_typ change to all children recursively
+    if (data.budget_typ !== undefined && result.rows[0]) {
+      const newBudgetTyp = result.rows[0].budget_typ;
+      // Fetch what the old type was before the update (the RETURNING row has the new value)
+      // We know a change happened if the user sent budget_typ, so cascade unconditionally
+      await cascadeBudgetTypToChildren(id, newBudgetTyp);
+    }
+
     return result.rows[0] || null;
   } catch (error: any) {
     logger.error('BuchhaltungService.updateKonto failed', { error, id });

backend/src/services/user.service.ts

@@ -322,6 +322,69 @@ class UserService {
     }
   }
 
+  /**
+   * Purge all data associated with a user, keeping the users record itself.
+   * Financial/audit records (buchhaltung, bestellung_historie, audit_log) are preserved.
+   */
+  async purgeUserData(userId: string, requestingUserId: string): Promise<Record<string, number>> {
+    if (userId === requestingUserId) {
+      throw new Error('Cannot purge your own data');
+    }
+
+    const user = await this.findById(userId);
+    if (!user) {
+      throw new Error('User not found');
+    }
+
+    const client = await pool.connect();
+    try {
+      await client.query('BEGIN');
+
+      const results: Record<string, number> = {};
+
+      // Helper to delete and track row counts
+      const purge = async (table: string, column = 'user_id') => {
+        const r = await client.query(`DELETE FROM ${table} WHERE ${column} = $1`, [userId]);
+        results[table] = r.rowCount ?? 0;
+      };
+
+      // User-owned data tables (DELETE rows)
+      await purge('notifications');
+      await purge('mitglieder_profile');
+      await purge('dienstgrad_verlauf');
+      await purge('atemschutz_traeger');
+      await purge('ausbildungen');
+      await purge('untersuchungen');
+      await purge('fahrgenehmigungen');
+      await purge('befoerderungen');
+      await purge('einsatz_personal');
+      await purge('uebung_teilnahmen');
+      await purge('veranstaltung_teilnahmen');
+      await purge('veranstaltung_ical_tokens');
+      await purge('fahrzeug_ical_tokens');
+      await purge('shop_anfragen', 'anfrager_id');
+
+      // Clear user preferences (widget layout, etc.)
+      await client.query(
+        `UPDATE users SET preferences = NULL, nextcloud_login_name = NULL, nextcloud_app_password = NULL WHERE id = $1`,
+        [userId]
+      );
+      results['preferences_cleared'] = 1;
+
+      await client.query('COMMIT');
+
+      logger.info('User data purged', { userId, by: requestingUserId, results });
+
+      return results;
+    } catch (error) {
+      await client.query('ROLLBACK');
+      logger.error('Error purging user data', { error, userId, requestingUserId });
+      throw error;
+    } finally {
+      client.release();
+    }
+  }
+
   /**
    * Sync Authentik groups for a user
    */

frontend/src/components/admin/UserOverviewTab.tsx

@@ -1,6 +1,13 @@
 import { useState, useMemo } from 'react';
 import {
   Box,
+  Button,
+  Dialog,
+  DialogActions,
+  DialogContent,
+  DialogContentText,
+  DialogTitle,
+  IconButton,
   Table,
   TableBody,
   TableCell,
@@ -11,11 +18,14 @@ import {
   Paper,
   TextField,
   Chip,
+  Tooltip,
   Typography,
   CircularProgress,
 } from '@mui/material';
-import { useQuery } from '@tanstack/react-query';
+import { DeleteSweep as DeleteSweepIcon } from '@mui/icons-material';
+import { useQuery, useQueryClient } from '@tanstack/react-query';
 import { adminApi } from '../../services/admin';
+import { useNotification } from '../../contexts/NotificationContext';
 import type { UserOverview } from '../../types/admin.types';
 
 function getRoleFromGroups(groups: string[] | null): string {
@@ -51,6 +61,10 @@ function UserOverviewTab() {
   const [search, setSearch] = useState('');
   const [sortKey, setSortKey] = useState<SortKey>('name');
   const [sortDir, setSortDir] = useState<SortDir>('asc');
+  const [purgeTarget, setPurgeTarget] = useState<UserOverview | null>(null);
+  const [purging, setPurging] = useState(false);
+  const queryClient = useQueryClient();
+  const { showSuccess, showError } = useNotification();
 
   const { data: users, isLoading, isError } = useQuery({
     queryKey: ['admin', 'users'],
@@ -90,6 +104,21 @@ function UserOverviewTab() {
     return result;
   }, [users, search, sortKey, sortDir]);
 
+  const handlePurge = async () => {
+    if (!purgeTarget) return;
+    setPurging(true);
+    try {
+      await adminApi.purgeUserData(purgeTarget.id);
+      showSuccess(`Daten von ${purgeTarget.name} wurden gelöscht.`);
+      queryClient.invalidateQueries({ queryKey: ['admin', 'users'] });
+    } catch {
+      showError('Daten konnten nicht gelöscht werden.');
+    } finally {
+      setPurging(false);
+      setPurgeTarget(null);
+    }
+  };
+
   if (isLoading) {
     return <Box sx={{ display: 'flex', justifyContent: 'center', p: 4 }}><CircularProgress /></Box>;
   }
@@ -148,6 +177,7 @@ function UserOverviewTab() {
                   Letzter Login
                 </TableSortLabel>
               </TableCell>
+              <TableCell align="right">Aktionen</TableCell>
             </TableRow>
           </TableHead>
           <TableBody>
@@ -177,11 +207,35 @@ function UserOverviewTab() {
                   />
                 </TableCell>
                 <TableCell>{formatRelativeTime(user.last_login_at)}</TableCell>
+                <TableCell align="right">
+                  <Tooltip title="Benutzerdaten löschen">
+                    <IconButton size="small" onClick={() => setPurgeTarget(user)}>
+                      <DeleteSweepIcon fontSize="small" />
+                    </IconButton>
+                  </Tooltip>
+                </TableCell>
               </TableRow>
             ))}
           </TableBody>
         </Table>
       </TableContainer>
+
+      <Dialog open={!!purgeTarget} onClose={() => !purging && setPurgeTarget(null)}>
+        <DialogTitle>Benutzerdaten löschen?</DialogTitle>
+        <DialogContent>
+          <DialogContentText>
+            Möchtest du alle persönlichen Daten von <strong>{purgeTarget?.name}</strong> löschen?
+            Das Benutzerkonto bleibt erhalten, aber Profil, Benachrichtigungen und Buchungen werden
+            unwiderruflich entfernt.
+          </DialogContentText>
+        </DialogContent>
+        <DialogActions>
+          <Button onClick={() => setPurgeTarget(null)} disabled={purging}>Abbrechen</Button>
+          <Button onClick={handlePurge} color="error" variant="contained" disabled={purging}>
+            {purging ? 'Wird gelöscht...' : 'Daten löschen'}
+          </Button>
+        </DialogActions>
+      </Dialog>
     </Box>
   );
 }

frontend/src/components/auth/FirstLoginDialog.tsx

@@ -0,0 +1,74 @@
+import { useState } from 'react';
+import {
+  Dialog,
+  DialogTitle,
+  DialogContent,
+  DialogActions,
+  Button,
+  TextField,
+  Typography,
+} from '@mui/material';
+import { membersService } from '../../services/members';
+
+interface Props {
+  open: boolean;
+  userId: string;
+  onClose: () => void;
+}
+
+export const FirstLoginDialog = ({ open, userId, onClose }: Props) => {
+  const [standesbuchnummer, setStandesbuchnummer] = useState('');
+  const [saving, setSaving] = useState(false);
+
+  const handleSave = async () => {
+    setSaving(true);
+    try {
+      if (standesbuchnummer.trim()) {
+        await membersService.updateMember(userId, {
+          fdisk_standesbuch_nr: standesbuchnummer.trim(),
+        });
+      }
+    } catch {
+      // non-fatal, user can update later in profile
+    } finally {
+      setSaving(false);
+      localStorage.setItem('firstLoginCompleted', 'true');
+      onClose();
+    }
+  };
+
+  const handleSkip = () => {
+    localStorage.setItem('firstLoginCompleted', 'true');
+    onClose();
+  };
+
+  return (
+    <Dialog open={open} maxWidth="sm" fullWidth>
+      <DialogTitle>Willkommen!</DialogTitle>
+      <DialogContent>
+        <Typography variant="body2" color="text.secondary" sx={{ mb: 2 }}>
+          Du wurdest erfolgreich registriert. Bitte gib deine Standesbuchnummer ein, damit dein
+          Profil zugeordnet werden kann. Dies kann auch später in deinen Profileinstellungen
+          ergänzt werden.
+        </Typography>
+        <TextField
+          label="Standesbuchnummer"
+          value={standesbuchnummer}
+          onChange={(e) => setStandesbuchnummer(e.target.value)}
+          fullWidth
+          size="small"
+          placeholder="z.B. 12345"
+          inputProps={{ maxLength: 32 }}
+        />
+      </DialogContent>
+      <DialogActions>
+        <Button onClick={handleSkip} color="inherit">
+          Überspringen
+        </Button>
+        <Button onClick={handleSave} variant="contained" disabled={saving}>
+          {saving ? 'Speichern...' : 'Speichern'}
+        </Button>
+      </DialogActions>
+    </Dialog>
+  );
+};

frontend/src/components/auth/LoginCallback.tsx

@@ -2,12 +2,15 @@ import React, { useEffect, useRef, useState } from 'react';
 import { useNavigate, useSearchParams } from 'react-router-dom';
 import { useAuth } from '../../contexts/AuthContext';
 import { Box, CircularProgress, Typography, Alert, Button } from '@mui/material';
+import { FirstLoginDialog } from './FirstLoginDialog';
 
 const LoginCallback: React.FC = () => {
   const navigate = useNavigate();
   const [searchParams] = useSearchParams();
-  const { login } = useAuth();
+  const { login, user } = useAuth();
   const [error, setError] = useState<string>('');
+  const [showFirstLogin, setShowFirstLogin] = useState(false);
+  const [redirectTo, setRedirectTo] = useState('/dashboard');
   const hasCalledLogin = useRef(false);
 
   useEffect(() => {
@@ -29,7 +32,7 @@ const LoginCallback: React.FC = () => {
       }
 
       try {
-        await login(code);
+        const result = await login(code);
         // Navigate to the originally intended page, falling back to the dashboard.
         // Validate that the stored path is a safe internal path: must start with '/'
         // but must NOT start with '//' (protocol-relative redirect).
@@ -39,7 +42,13 @@ const LoginCallback: React.FC = () => {
             ? rawFrom
             : '/dashboard';
         sessionStorage.removeItem('auth_redirect_from');
+
+        if (result.isNewUser && !localStorage.getItem('firstLoginCompleted')) {
+          setRedirectTo(from);
+          setShowFirstLogin(true);
+        } else {
           navigate(from, { replace: true });
+        }
       } catch (err) {
         console.error('Login callback error:', err);
         const is429 = err && typeof err === 'object' && 'status' in err && (err as any).status === 429;
@@ -99,10 +108,20 @@ const LoginCallback: React.FC = () => {
         gap: 2,
       }}
     >
+      {showFirstLogin && user ? (
+        <FirstLoginDialog
+          open={showFirstLogin}
+          userId={user.id}
+          onClose={() => navigate(redirectTo, { replace: true })}
+        />
+      ) : (
+        <>
           <CircularProgress size={60} />
           <Typography variant="h6" color="text.secondary">
             Anmeldung wird abgeschlossen...
           </Typography>
+        </>
+      )}
     </Box>
   );
 };

frontend/src/components/common/PageBreadcrumbs.tsx

@@ -0,0 +1,44 @@
+import { Breadcrumbs, Typography, Link as MuiLink } from '@mui/material';
+import NavigateNextIcon from '@mui/icons-material/NavigateNext';
+import { Link } from 'react-router-dom';
+
+export interface BreadcrumbItem {
+  label: string;
+  href?: string;
+}
+
+interface Props {
+  items: BreadcrumbItem[];
+}
+
+export const PageBreadcrumbs = ({ items }: Props) => {
+  return (
+    <Breadcrumbs
+      separator={<NavigateNextIcon fontSize="small" />}
+      sx={{ mb: 2, fontSize: '0.8125rem' }}
+    >
+      {items.map((item, index) => {
+        const isLast = index === items.length - 1;
+        if (isLast || !item.href) {
+          return (
+            <Typography key={index} variant="body2" color="text.primary" fontWeight={500}>
+              {item.label}
+            </Typography>
+          );
+        }
+        return (
+          <MuiLink
+            key={index}
+            component={Link}
+            to={item.href}
+            underline="hover"
+            color="text.secondary"
+            variant="body2"
+          >
+            {item.label}
+          </MuiLink>
+        );
+      })}
+    </Breadcrumbs>
+  );
+};

frontend/src/components/common/index.ts

@@ -0,0 +1,2 @@
+export { PageBreadcrumbs } from './PageBreadcrumbs';
+export type { BreadcrumbItem } from './PageBreadcrumbs';

frontend/src/components/dashboard/NextcloudTalkWidget.tsx

@@ -1,7 +1,5 @@
 import React, { useState, useRef, useEffect, useCallback } from 'react';
 import {
-  Card,
-  CardContent,
   Typography,
   Box,
   Chip,
@@ -20,6 +18,7 @@ import { nextcloudApi } from '../../services/nextcloud';
 import type { NextcloudConversation } from '../../types/nextcloud.types';
 import { safeOpenUrl } from '../../utils/safeOpenUrl';
 import { useCountUp } from '../../hooks/useCountUp';
+import { WidgetCard } from '../templates/WidgetCard';
 
 const POLL_INTERVAL = 2000;
 const POLL_TIMEOUT = 5 * 60 * 1000;
@@ -183,22 +182,8 @@ const NextcloudTalkWidget: React.FC = () => {
     }
   };
 
-  return (
+  const headerAction = (
-    <Card
+    <Box sx={{ display: 'flex', alignItems: 'center', gap: 0.5 }}>
-      sx={{
-        height: '100%',
-        transition: 'all 0.3s ease',
-        '&:hover': {
-          boxShadow: 3,
-        },
-      }}
-    >
-      <CardContent>
-        <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 2 }}>
-          <Forum color="primary" />
-          <Typography variant="h6" sx={{ flexGrow: 1 }}>
-            Nextcloud Talk
-          </Typography>
       {connected && totalUnread > 0 && (
         <Chip
           label={`${animatedUnread} ungelesen`}
@@ -215,7 +200,16 @@ const NextcloudTalkWidget: React.FC = () => {
         </Tooltip>
       )}
     </Box>
+  );
 
+  return (
+    <WidgetCard
+      title="Nextcloud Talk"
+      icon={<Forum />}
+      action={headerAction}
+      noPadding
+    >
+      <Box sx={{ px: 2.5, pb: 2.5 }}>
         {isLoading && (
           <Box>
             {[1, 2, 3].map((n) => (
@@ -276,8 +270,8 @@ const NextcloudTalkWidget: React.FC = () => {
             ))}
           </Box>
         )}
-      </CardContent>
+      </Box>
-    </Card>
+    </WidgetCard>
   );
 };
 

frontend/src/contexts/AuthContext.tsx

@@ -1,5 +1,5 @@
 import React, { createContext, useCallback, useContext, useState, useEffect, ReactNode } from 'react';
-import { AuthContextType, AuthState } from '../types/auth.types';
+import { AuthContextType, AuthState, LoginResult } from '../types/auth.types';
 import { authService } from '../services/auth';
 import { getToken, setToken, removeToken, getUser, setUser, removeUser, setRefreshToken, removeRefreshToken } from '../utils/storage';
 import { useNotification } from './NotificationContext';
@@ -67,11 +67,11 @@ export const AuthProvider: React.FC<AuthProviderProps> = ({ children }) => {
     initializeAuth();
   }, []);
 
-  const login = useCallback(async (code: string): Promise<void> => {
+  const login = useCallback(async (code: string): Promise<LoginResult> => {
     try {
       setState((prev) => ({ ...prev, isLoading: true }));
 
-      const { token, refreshToken, user } = await authService.handleCallback(code);
+      const { token, refreshToken, user, isNewUser } = await authService.handleCallback(code);
 
       // Save to localStorage
       setToken(token);
@@ -88,6 +88,8 @@ export const AuthProvider: React.FC<AuthProviderProps> = ({ children }) => {
 
       // Show success notification
       notification.showSuccess('Anmeldung erfolgreich');
+
+      return { isNewUser };
     } catch (error) {
       console.error('Login failed:', error);
       setState({

frontend/src/pages/AdminSettings.tsx

@@ -32,6 +32,7 @@ import {
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import { Navigate } from 'react-router-dom';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import { usePermissionContext } from '../contexts/PermissionContext';
 import { useNotification } from '../contexts/NotificationContext';
 import { settingsApi } from '../services/settings';
@@ -293,6 +294,10 @@ function AdminSettings() {
   return (
     <DashboardLayout>
       <Container maxWidth="lg">
+        <PageBreadcrumbs items={[
+          { label: 'Admin', href: '/admin' },
+          { label: 'Einstellungen' },
+        ]} />
         <Typography variant="h4" gutterBottom sx={{ mb: 4 }}>
           Admin-Einstellungen
         </Typography>

frontend/src/pages/AusruestungDetail.tsx

@@ -779,6 +779,10 @@ function AusruestungDetailPage() {
         <DetailLayout
           title={equipment.bezeichnung}
           backTo="/ausruestung"
+          breadcrumbs={[
+            { label: 'Ausrüstung', href: '/ausruestung' },
+            { label: equipment.bezeichnung },
+          ]}
           tabs={tabs}
           actions={
             <Box sx={{ display: 'flex', alignItems: 'center', gap: 1 }}>

frontend/src/pages/AusruestungsanfrageArtikelDetail.tsx

@@ -11,6 +11,7 @@ import {
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import { useParams, useNavigate } from 'react-router-dom';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import { useNotification } from '../contexts/NotificationContext';
 import { usePermissionContext } from '../contexts/PermissionContext';
 import { ausruestungsanfrageApi } from '../services/ausruestungsanfrage';
@@ -285,6 +286,10 @@ export default function AusruestungsanfrageArtikelDetail() {
 
   return (
     <DashboardLayout>
+      <PageBreadcrumbs items={[
+        { label: 'Ausrüstungsanfragen', href: '/ausruestungsanfrage' },
+        { label: isCreate ? 'Neuer Katalogartikel' : (artikel?.bezeichnung ?? 'Artikel') },
+      ]} />
       {/* Header */}
       <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 3 }}>
         <IconButton onClick={() => navigate('/ausruestungsanfrage?tab=2')}>

frontend/src/pages/AusruestungsanfrageDetail.tsx

@@ -13,6 +13,7 @@ import {
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import { useParams, useNavigate } from 'react-router-dom';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import { useNotification } from '../contexts/NotificationContext';
 import { usePermissionContext } from '../contexts/PermissionContext';
 import { useAuth } from '../contexts/AuthContext';
@@ -193,6 +194,10 @@ export default function AusruestungsanfrageDetail() {
 
   return (
     <DashboardLayout>
+      <PageBreadcrumbs items={[
+        { label: 'Ausrüstungsanfragen', href: '/ausruestungsanfrage' },
+        { label: anfrage ? `Anfrage ${formatOrderId(anfrage)}` : 'Anfrage' },
+      ]} />
       {/* Header */}
       <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 3 }}>
         <IconButton onClick={() => navigate('/ausruestungsanfrage')}>

frontend/src/pages/AusruestungsanfrageNeu.tsx

@@ -7,6 +7,7 @@ import { ArrowBack, Add as AddIcon, Delete as DeleteIcon } from '@mui/icons-mate
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import { useNavigate } from 'react-router-dom';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import { useNotification } from '../contexts/NotificationContext';
 import { usePermissionContext } from '../contexts/PermissionContext';
 import { ausruestungsanfrageApi } from '../services/ausruestungsanfrage';
@@ -168,6 +169,10 @@ export default function AusruestungsanfrageNeu() {
 
   return (
     <DashboardLayout>
+      <PageBreadcrumbs items={[
+        { label: 'Ausrüstungsanfragen', href: '/ausruestungsanfrage' },
+        { label: 'Neue Bestellung' },
+      ]} />
       {/* Header */}
       <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 3 }}>
         <IconButton onClick={() => navigate('/ausruestungsanfrage')}>

frontend/src/pages/AusruestungsanfrageZuBestellung.tsx

@@ -14,6 +14,7 @@ import {
 import { useParams, useNavigate } from 'react-router-dom';
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import { useNotification } from '../contexts/NotificationContext';
 import { usePermissionContext } from '../contexts/PermissionContext';
 import { ausruestungsanfrageApi } from '../services/ausruestungsanfrage';
@@ -236,6 +237,11 @@ export default function AusruestungsanfrageZuBestellung() {
   return (
     <DashboardLayout>
       <Box sx={{ maxWidth: 960, mx: 'auto', px: 2, py: 3 }}>
+        <PageBreadcrumbs items={[
+          { label: 'Ausrüstungsanfragen', href: '/ausruestungsanfrage' },
+          { label: anfrage.bezeichnung || `Anfrage ${formatOrderId(anfrage)}`, href: `/ausruestungsanfrage/${requestId}` },
+          { label: 'Bestellen' },
+        ]} />
 
         {/* ── Header ── */}
         <Box sx={{ display: 'flex', alignItems: 'center', gap: 1.5, mb: 3 }}>

frontend/src/pages/BestellungDetail.tsx

@@ -673,6 +673,10 @@ export default function BestellungDetail() {
       <PageHeader
         title={bestellung.bezeichnung}
         backTo="/bestellungen"
+        breadcrumbs={[
+          { label: 'Bestellungen', href: '/bestellungen' },
+          { label: bestellung.bezeichnung },
+        ]}
         actions={
           <Box sx={{ display: 'flex', alignItems: 'center', gap: 1 }}>
             {canExport && !editMode && (

frontend/src/pages/BuchhaltungBankkontoDetail.tsx

@@ -23,6 +23,7 @@ import { ArrowBack } from '@mui/icons-material';
 import { useQuery } from '@tanstack/react-query';
 import { useParams, useNavigate } from 'react-router-dom';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import { buchhaltungApi } from '../services/buchhaltung';
 import { TRANSAKTION_TYP_LABELS } from '../types/buchhaltung.types';
 import type { BankkontoStatementRow } from '../types/buchhaltung.types';
@@ -61,6 +62,10 @@ export default function BuchhaltungBankkontoDetail() {
 
   return (
     <DashboardLayout>
+      <PageBreadcrumbs items={[
+        { label: 'Buchhaltung', href: '/buchhaltung' },
+        { label: data?.bankkonto?.bezeichnung || 'Bankkonto' },
+      ]} />
       <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 3 }}>
         <Tooltip title="Zurueck">
           <IconButton onClick={() => navigate('/buchhaltung?tab=2')}>

frontend/src/pages/BuchhaltungKontoDetail.tsx

@@ -9,6 +9,7 @@ import {
 } from '@mui/material';
 import { ArrowBack, KeyboardArrowDown, KeyboardArrowUp } from '@mui/icons-material';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import { buchhaltungApi } from '../services/buchhaltung';
 import { AUSGABEN_TYP_LABELS } from '../types/buchhaltung.types';
 import type { AusgabenTyp, BuchhaltungAudit } from '../types/buchhaltung.types';
@@ -132,6 +133,10 @@ export default function BuchhaltungKontoDetail() {
   return (
     <DashboardLayout>
       <Box sx={{ p: 3 }}>
+        <PageBreadcrumbs items={[
+          { label: 'Buchhaltung', href: '/buchhaltung' },
+          { label: `${konto.kontonummer} — ${konto.bezeichnung}` },
+        ]} />
         <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 3 }}>
           <Button startIcon={<ArrowBack />} onClick={() => navigate('/buchhaltung')}>
             Zurück

frontend/src/pages/BuchhaltungKontoManage.tsx

@@ -8,6 +8,7 @@ import {
 } from '@mui/material';
 import { ArrowBack, Delete, Edit, Save, Cancel } from '@mui/icons-material';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import { buchhaltungApi } from '../services/buchhaltung';
 import { useNotification } from '../contexts/NotificationContext';
 import type { KontoFormData, BudgetTyp } from '../types/buchhaltung.types';
@@ -172,6 +173,11 @@ export default function BuchhaltungKontoManage() {
 
   return (
     <DashboardLayout>
+      <PageBreadcrumbs items={[
+        { label: 'Buchhaltung', href: '/buchhaltung' },
+        { label: `${konto.kontonummer} — ${konto.bezeichnung}`, href: `/buchhaltung/konto/${id}` },
+        { label: 'Verwalten' },
+      ]} />
       <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 3 }}>
         <Button startIcon={<ArrowBack />} onClick={() => navigate('/buchhaltung?tab=2')}>
           Zurück

frontend/src/pages/ChecklistAusfuehrung.tsx

@@ -19,6 +19,7 @@ import { ArrowBack, CheckCircle, Cancel, RemoveCircle } from '@mui/icons-materia
 import { useNavigate, useParams, useSearchParams } from 'react-router-dom';
 import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import { usePermissionContext } from '../contexts/PermissionContext';
 import { useNotification } from '../contexts/NotificationContext';
 import { checklistenApi } from '../services/checklisten';
@@ -243,6 +244,10 @@ export default function ChecklistAusfuehrung() {
 
   return (
     <DashboardLayout>
+      <PageBreadcrumbs items={[
+        { label: 'Checklisten', href: '/checklisten' },
+        { label: execution.vorlage_name ?? 'Checkliste' },
+      ]} />
       <Button startIcon={<ArrowBack />} onClick={() => navigate('/checklisten')} sx={{ mb: 2 }} size="small">
         Checklisten
       </Button>

frontend/src/pages/EinsatzDetail.tsx

@@ -284,6 +284,10 @@ function EinsatzDetail() {
           title={`Einsatz ${einsatz.einsatz_nr}`}
           subtitle={address || undefined}
           backTo="/einsaetze"
+          breadcrumbs={[
+            { label: 'Einsätze', href: '/einsaetze' },
+            { label: `Einsatz ${einsatz.einsatz_nr}` },
+          ]}
           actions={
             <Stack direction="row" spacing={1} alignItems="center">
               <Chip

frontend/src/pages/FahrzeugDetail.tsx

@@ -1006,6 +1006,10 @@ function FahrzeugDetail() {
         <DetailLayout
           title={titleText}
           backTo="/fahrzeuge"
+          breadcrumbs={[
+            { label: 'Fahrzeuge', href: '/fahrzeuge' },
+            { label: titleText },
+          ]}
           tabs={tabs}
           actions={
             <Box sx={{ display: 'flex', alignItems: 'center', gap: 1 }}>

frontend/src/pages/HaushaltsplanDetail.tsx

@@ -1,5 +1,6 @@
 import { useState } from 'react';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import {
   Alert,
   Box,
@@ -143,6 +144,10 @@ export default function HaushaltsplanDetail() {
 
   return (
     <DashboardLayout>
+      <PageBreadcrumbs items={[
+        { label: 'Haushaltsplan', href: '/haushaltsplan' },
+        { label: planung.bezeichnung },
+      ]} />
       <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 3 }}>
         <IconButton onClick={() => navigate('/haushaltsplan')}><ArrowBack /></IconButton>
         <Typography variant="h4" sx={{ flexGrow: 1 }}>{planung.bezeichnung}</Typography>

frontend/src/pages/IssueDetail.tsx

@@ -264,6 +264,10 @@ export default function IssueDetail() {
         <PageHeader
           title={`${formatIssueId(issue)} — ${issue.titel}`}
           backTo="/issues"
+          breadcrumbs={[
+            { label: 'Issues', href: '/issues' },
+            { label: `${formatIssueId(issue)} — ${issue.titel}` },
+          ]}
           actions={
             <Chip
               label={getStatusLabel(statuses, issue.status)}

frontend/src/pages/MitgliedDetail.tsx

@@ -419,6 +419,10 @@ function MitgliedDetail() {
         <PageHeader
           title={displayName}
           backTo="/mitglieder"
+          breadcrumbs={[
+            { label: 'Mitglieder', href: '/mitglieder' },
+            { label: displayName },
+          ]}
         />
 
         {/* Header card */}

frontend/src/pages/UebungDetail.tsx

@@ -42,6 +42,7 @@ import {
 } from '@mui/icons-material';
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import { usePermissionContext } from '../contexts/PermissionContext';
 import { trainingApi } from '../services/training';
 import type { TeilnahmeStatus, UebungTyp, Teilnahme } from '../types/training.types';
@@ -332,6 +333,10 @@ export default function UebungDetail() {
   return (
     <DashboardLayout>
       <Box sx={{ maxWidth: 720, mx: 'auto' }}>
+        <PageBreadcrumbs items={[
+          { label: 'Kalender', href: '/kalender' },
+          { label: event.titel || 'Übung' },
+        ]} />
         {/* Back button */}
         <Button
           startIcon={<BackIcon />}

frontend/src/pages/VeranstaltungKategorien.tsx

@@ -34,6 +34,7 @@ import {
   Category as CategoryIcon,
 } from '@mui/icons-material';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
+import { PageBreadcrumbs } from '../components/common';
 import { usePermissionContext } from '../contexts/PermissionContext';
 import { useNotification } from '../contexts/NotificationContext';
 import { eventsApi } from '../services/events';
@@ -339,6 +340,10 @@ export default function VeranstaltungKategorien() {
   return (
     <DashboardLayout>
       <Container maxWidth="lg" sx={{ py: 3 }}>
+        <PageBreadcrumbs items={[
+          { label: 'Veranstaltungen', href: '/veranstaltungen' },
+          { label: 'Kategorien' },
+        ]} />
         {/* Header */}
         <Box
           sx={{

frontend/src/services/admin.ts

@@ -31,4 +31,5 @@ export const adminApi = {
   fdiskSyncLogs: () => api.get<ApiResponse<FdiskSyncLogsResponse>>('/api/admin/fdisk-sync/logs').then(r => r.data.data),
   fdiskSyncTrigger: (force = false) => api.post<ApiResponse<{ started: boolean }>>('/api/admin/fdisk-sync/trigger', { force }).then(r => r.data.data),
   purgeFdiskData: (userId: string) => api.delete<ApiResponse<{ profileFieldsCleared: number; ausbildungen: number; befoerderungen: number; untersuchungen: number; fahrgenehmigungen: number }>>(`/api/admin/users/${userId}/fdisk-data`).then(r => r.data.data),
+  purgeUserData: (userId: string) => api.post<ApiResponse<Record<string, number>>>(`/api/admin/users/${userId}/purge-data`).then(r => r.data.data),
 };

frontend/src/services/auth.ts

@@ -8,6 +8,7 @@ export interface AuthCallbackResponse {
   token: string;
   refreshToken: string;
   user: User;
+  isNewUser?: boolean;
 }
 
 // The backend returns camelCase field names; map them to the snake_case User type.
@@ -45,7 +46,7 @@ export const authService = {
     const response = await api.post<{
       success: boolean;
       message: string;
-      data: { accessToken: string; refreshToken: string; user: Record<string, unknown> };
+      data: { accessToken: string; refreshToken: string; isNewUser?: boolean; user: Record<string, unknown> };
     }>('/api/auth/callback', {
       code,
       redirect_uri: REDIRECT_URI,
@@ -54,6 +55,7 @@ export const authService = {
       token: response.data.data.accessToken,
       refreshToken: response.data.data.refreshToken,
       user: mapBackendUser(response.data.data.user),
+      isNewUser: response.data.data.isNewUser,
     };
   },
 

frontend/src/types/auth.types.ts

@@ -21,8 +21,12 @@ export interface AuthState {
   isLoading: boolean;
 }
 
+export interface LoginResult {
+  isNewUser?: boolean;
+}
+
 export interface AuthContextType extends AuthState {
-  login: (code: string) => Promise<void>;
+  login: (code: string) => Promise<LoginResult>;
   logout: () => void;
   refreshAuth: () => Promise<void>;
 }