feat(admin): centralize tool & module settings in Werkzeuge tab with per-tool permissions, DB-backed config, connection tests, and cog-button navigation

frontend/src/pages/Chat.tsx

@@ -1,10 +1,14 @@
 import React from 'react';
 import Box from '@mui/material/Box';
 import Typography from '@mui/material/Typography';
-import { Link } from 'react-router-dom';
+import IconButton from '@mui/material/IconButton';
+import Tooltip from '@mui/material/Tooltip';
+import { Link, useNavigate } from 'react-router-dom';
 import { useQueryClient } from '@tanstack/react-query';
+import { Settings } from '@mui/icons-material';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
 import { useChat } from '../contexts/ChatContext';
+import { usePermissionContext } from '../contexts/PermissionContext';
 import { nextcloudApi } from '../services/nextcloud';
 import { notificationsApi } from '../services/notifications';
 import ChatRoomList from '../components/chat/ChatRoomList';
@@ -12,6 +16,8 @@ import ChatMessageView from '../components/chat/ChatMessageView';
 
 const ChatContent: React.FC = () => {
   const { rooms, selectedRoomToken, connected } = useChat();
+  const { hasPermission } = usePermissionContext();
+  const navigate = useNavigate();
   const queryClient = useQueryClient();
   const markedRoomsRef = React.useRef(new Set<string>());
 
@@ -44,16 +50,27 @@ const ChatContent: React.FC = () => {
   }, [selectedRoomToken, queryClient]);
 
   return (
-    <Box
-      sx={{
-        height: 'calc(100vh - 112px)',
-        display: 'flex',
-        border: 1,
-        borderColor: 'divider',
-        borderRadius: 1,
-        overflow: 'hidden',
-      }}
-    >
+    <Box sx={{ display: 'flex', flexDirection: 'column', height: 'calc(100vh - 112px)' }}>
+      {hasPermission('nextcloud:configure') && (
+        <Box sx={{ display: 'flex', justifyContent: 'flex-end', px: 1 }}>
+          <Tooltip title="Einstellungen">
+            <IconButton size="small" onClick={() => navigate('/admin/settings?tab=1&subtab=nextcloud')}>
+              <Settings fontSize="small" />
+            </IconButton>
+          </Tooltip>
+        </Box>
+      )}
+      <Box
+        sx={{
+          flex: 1,
+          display: 'flex',
+          border: 1,
+          borderColor: 'divider',
+          borderRadius: 1,
+          overflow: 'hidden',
+          minHeight: 0,
+        }}
+      >
       {!connected ? (
         <Box sx={{ p: 3, display: 'flex', alignItems: 'center' }}>
           <Typography variant="body1" color="text.secondary">
@@ -89,6 +106,7 @@ const ChatContent: React.FC = () => {
           </Box>
         </>
       )}
+      </Box>
     </Box>
   );
 };