feat: add configurable permissions system with admin panel

Adds a full permissions management feature allowing admins to control
who can perform actions across the app (trip CRUD, files, places,
budget, packing, reservations, collab, members, share links).

- New server/src/services/permissions.ts: 16 configurable actions,
  in-memory cache, checkPermission() helper, backwards-compatible
  defaults matching upstream behaviour
- GET/PUT /admin/permissions endpoints; permissions loaded into
  app-config response so clients have them on startup
- checkPermission() applied to all mutating route handlers across
  10 server route files; getTripOwnerId() helper eliminates repeated
  inline DB queries; trips.ts and files.ts now reuse canAccessTrip()
  result to avoid redundant DB round-trips
- New client/src/store/permissionsStore.ts: Zustand store +
  useCanDo() hook; TripOwnerContext type accepts both Trip and
  DashboardTrip shapes without casting at call sites
- New client/src/components/Admin/PermissionsPanel.tsx: categorised
  UI with per-action dropdowns, customised badge, save/reset
- AdminPage, DashboardPage, FileManager, PlacesSidebar,
  TripMembersModal gated via useCanDo(); no prop drilling
- 46 perm.* translation keys added to all 12 language files

client/src/components/Admin/PermissionsPanel.tsx

@@ -0,0 +1,169 @@
+import React, { useEffect, useState, useMemo } from 'react'
+import { adminApi } from '../../api/client'
+import { useTranslation } from '../../i18n'
+import { usePermissionsStore, PermissionLevel } from '../../store/permissionsStore'
+import { useToast } from '../shared/Toast'
+import { Save, Loader2, RotateCcw } from 'lucide-react'
+import CustomSelect from '../shared/CustomSelect'
+
+interface PermissionEntry {
+  key: string
+  level: PermissionLevel
+  defaultLevel: PermissionLevel
+  allowedLevels: PermissionLevel[]
+}
+
+const LEVEL_LABELS: Record<string, string> = {
+  admin: 'perm.level.admin',
+  trip_owner: 'perm.level.tripOwner',
+  trip_member: 'perm.level.tripMember',
+  everybody: 'perm.level.everybody',
+}
+
+const CATEGORIES = [
+  { id: 'trip', keys: ['trip_create', 'trip_edit', 'trip_delete', 'trip_archive', 'trip_cover_upload'] },
+  { id: 'members', keys: ['member_manage'] },
+  { id: 'files', keys: ['file_upload', 'file_edit', 'file_delete'] },
+  { id: 'content', keys: ['place_edit', 'day_edit', 'reservation_edit'] },
+  { id: 'extras', keys: ['budget_edit', 'packing_edit', 'collab_edit', 'share_manage'] },
+]
+
+export default function PermissionsPanel(): React.ReactElement {
+  const { t } = useTranslation()
+  const toast = useToast()
+  const [entries, setEntries] = useState<PermissionEntry[]>([])
+  const [values, setValues] = useState<Record<string, PermissionLevel>>({})
+  const [loading, setLoading] = useState(true)
+  const [saving, setSaving] = useState(false)
+  const [dirty, setDirty] = useState(false)
+
+  useEffect(() => {
+    loadPermissions()
+  }, [])
+
+  const loadPermissions = async () => {
+    setLoading(true)
+    try {
+      const data = await adminApi.getPermissions()
+      setEntries(data.permissions)
+      const vals: Record<string, PermissionLevel> = {}
+      for (const p of data.permissions) vals[p.key] = p.level
+      setValues(vals)
+      setDirty(false)
+    } catch {
+      toast.error(t('common.error'))
+    } finally {
+      setLoading(false)
+    }
+  }
+
+  const handleChange = (key: string, level: PermissionLevel) => {
+    setValues(prev => ({ ...prev, [key]: level }))
+    setDirty(true)
+  }
+
+  const handleSave = async () => {
+    setSaving(true)
+    try {
+      const data = await adminApi.updatePermissions(values)
+      if (data.permissions) {
+        usePermissionsStore.getState().setPermissions(data.permissions)
+      }
+      setDirty(false)
+      toast.success(t('perm.saved'))
+    } catch {
+      toast.error(t('common.error'))
+    } finally {
+      setSaving(false)
+    }
+  }
+
+  const handleReset = () => {
+    const defaults: Record<string, PermissionLevel> = {}
+    for (const p of entries) defaults[p.key] = p.defaultLevel
+    setValues(defaults)
+    setDirty(true)
+  }
+
+  if (loading) {
+    return (
+      <div className="p-8 text-center">
+        <div className="w-8 h-8 border-2 border-slate-200 border-t-slate-900 rounded-full animate-spin mx-auto" />
+      </div>
+    )
+  }
+
+  const entryMap = useMemo(() => new Map(entries.map(e => [e.key, e])), [entries])
+
+  return (
+    <div className="space-y-6">
+      <div className="bg-white rounded-xl border border-slate-200 overflow-hidden">
+        <div className="px-6 py-4 border-b border-slate-100 flex items-center justify-between">
+          <div>
+            <h2 className="font-semibold text-slate-900">{t('perm.title')}</h2>
+            <p className="text-xs text-slate-400 mt-0.5">{t('perm.subtitle')}</p>
+          </div>
+          <div className="flex items-center gap-2">
+            <button
+              onClick={handleReset}
+              disabled={saving}
+              className="flex items-center gap-1.5 px-3 py-1.5 text-sm border border-slate-300 rounded-lg hover:bg-slate-50 disabled:opacity-40 transition-colors"
+            >
+              <RotateCcw className="w-3.5 h-3.5" />
+              {t('perm.resetDefaults')}
+            </button>
+            <button
+              onClick={handleSave}
+              disabled={saving || !dirty}
+              className="flex items-center gap-1.5 px-3 py-1.5 text-sm bg-slate-900 text-white rounded-lg hover:bg-slate-700 disabled:bg-slate-400 transition-colors"
+            >
+              {saving ? <Loader2 className="w-3.5 h-3.5 animate-spin" /> : <Save className="w-3.5 h-3.5" />}
+              {t('common.save')}
+            </button>
+          </div>
+        </div>
+
+        <div className="divide-y divide-slate-100">
+          {CATEGORIES.map(cat => (
+            <div key={cat.id} className="px-6 py-4">
+              <h3 className="text-xs font-semibold text-slate-500 uppercase tracking-wider mb-3">
+                {t(`perm.cat.${cat.id}`)}
+              </h3>
+              <div className="space-y-3">
+                {cat.keys.map(key => {
+                  const entry = entryMap.get(key)
+                  if (!entry) return null
+                  const currentLevel = values[key] || entry.defaultLevel
+                  const isDefault = currentLevel === entry.defaultLevel
+                  return (
+                    <div key={key} className="flex items-center justify-between gap-4">
+                      <div className="flex-1 min-w-0">
+                        <p className="text-sm font-medium text-slate-700">{t(`perm.action.${key}`)}</p>
+                        <p className="text-xs text-slate-400 mt-0.5">{t(`perm.actionHint.${key}`)}</p>
+                      </div>
+                      <div className="flex items-center gap-2">
+                        {!isDefault && (
+                          <span className="text-[10px] font-medium px-1.5 py-0.5 rounded-full bg-amber-100 text-amber-700">
+                            {t('perm.customized')}
+                          </span>
+                        )}
+                        <CustomSelect
+                          value={currentLevel}
+                          onChange={(val) => handleChange(key, val as PermissionLevel)}
+                          options={entry.allowedLevels.map(l => ({
+                            value: l,
+                            label: t(LEVEL_LABELS[l] || l),
+                          }))}
+                        />
+                      </div>
+                    </div>
+                  )
+                })}
+              </div>
+            </div>
+          ))}
+        </div>
+      </div>
+    </div>
+  )
+}

client/src/components/Files/FileManager.tsx

@@ -6,6 +6,8 @@ import { useToast } from '../shared/Toast'
 import { useTranslation } from '../../i18n'
 import { filesApi } from '../../api/client'
 import type { Place, Reservation, TripFile, Day, AssignmentsMap } from '../../types'
+import { useCanDo } from '../../store/permissionsStore'
+import { useTripStore } from '../../store/tripStore'
 
 function authUrl(url: string): string {
   const token = localStorage.getItem('auth_token')
@@ -159,6 +161,8 @@ export default function FileManager({ files = [], onUpload, onDelete, onUpdate,
   const [trashFiles, setTrashFiles] = useState<TripFile[]>([])
   const [loadingTrash, setLoadingTrash] = useState(false)
   const toast = useToast()
+  const can = useCanDo()
+  const trip = useTripStore((s) => s.trip)
   const { t, locale } = useTranslation()
 
   const loadTrash = useCallback(async () => {
@@ -710,7 +714,7 @@ export default function FileManager({ files = [], onUpload, onDelete, onUpdate,
       ) : (
         <>
           {/* Upload zone */}
-          <div
+          {can('file_upload', trip) && <div
             {...getRootProps()}
             style={{
               margin: '16px 16px 0', border: '2px dashed', borderRadius: 14, padding: '20px 16px',
@@ -735,7 +739,7 @@ export default function FileManager({ files = [], onUpload, onDelete, onUpdate,
                 </p>
               </>
             )}
-          </div>
+          </div>}
 
           {/* Filter tabs */}
           <div style={{ display: 'flex', gap: 4, padding: '12px 16px 0', flexShrink: 0, flexWrap: 'wrap' }}>

client/src/components/Planner/PlacesSidebar.tsx

@@ -11,6 +11,7 @@ import CustomSelect from '../shared/CustomSelect'
 import { useContextMenu, ContextMenu } from '../shared/ContextMenu'
 import { placesApi } from '../../api/client'
 import { useTripStore } from '../../store/tripStore'
+import { useCanDo } from '../../store/permissionsStore'
 import type { Place, Category, Day, AssignmentsMap } from '../../types'
 
 interface PlacesSidebarProps {
@@ -38,7 +39,10 @@ const PlacesSidebar = React.memo(function PlacesSidebar({
   const toast = useToast()
   const ctxMenu = useContextMenu()
   const gpxInputRef = useRef<HTMLInputElement>(null)
-  const tripStore = useTripStore()
+  const trip = useTripStore((s) => s.trip)
+  const loadTrip = useTripStore((s) => s.loadTrip)
+  const can = useCanDo()
+  const canEditPlaces = can('place_edit', trip)
 
   const handleGpxImport = async (e: React.ChangeEvent<HTMLInputElement>) => {
     const file = e.target.files?.[0]
@@ -46,7 +50,7 @@ const PlacesSidebar = React.memo(function PlacesSidebar({
     e.target.value = ''
     try {
       const result = await placesApi.importGpx(tripId, file)
-      await tripStore.loadTrip(tripId)
+      await loadTrip(tripId)
       toast.success(t('places.gpxImported', { count: result.count }))
     } catch (err: any) {
       toast.error(err?.response?.data?.error || t('places.gpxError'))
@@ -88,7 +92,7 @@ const PlacesSidebar = React.memo(function PlacesSidebar({
     <div style={{ display: 'flex', flexDirection: 'column', height: '100%', fontFamily: "-apple-system, BlinkMacSystemFont, 'SF Pro Text', system-ui, sans-serif" }}>
       {/* Kopfbereich */}
       <div style={{ padding: '14px 16px 10px', borderBottom: '1px solid var(--border-faint)', flexShrink: 0 }}>
-        <button
+        {canEditPlaces && <button
           onClick={onAddPlace}
           style={{
             display: 'flex', alignItems: 'center', justifyContent: 'center', gap: 6,
@@ -98,7 +102,8 @@ const PlacesSidebar = React.memo(function PlacesSidebar({
           }}
         >
           <Plus size={14} strokeWidth={2} /> {t('places.addPlace')}
-        </button>
+        </button>}
+        {canEditPlaces && <>
         <input ref={gpxInputRef} type="file" accept=".gpx" style={{ display: 'none' }} onChange={handleGpxImport} />
         <button
           onClick={() => gpxInputRef.current?.click()}
@@ -112,6 +117,7 @@ const PlacesSidebar = React.memo(function PlacesSidebar({
         >
           <Upload size={11} strokeWidth={2} /> {t('places.importGpx')}
         </button>
+        </>}
 
         {/* Filter-Tabs */}
         <div style={{ display: 'flex', gap: 4, marginBottom: 8 }}>
@@ -252,12 +258,12 @@ const PlacesSidebar = React.memo(function PlacesSidebar({
                   }
                 }}
                 onContextMenu={e => ctxMenu.open(e, [
-                  onEditPlace && { label: t('common.edit'), icon: Pencil, onClick: () => onEditPlace(place) },
+                  canEditPlaces && { label: t('common.edit'), icon: Pencil, onClick: () => onEditPlace(place) },
                   selectedDayId && { label: t('planner.addToDay'), icon: CalendarDays, onClick: () => onAssignToDay(place.id, selectedDayId) },
                   place.website && { label: t('inspector.website'), icon: ExternalLink, onClick: () => window.open(place.website, '_blank') },
                   (place.lat && place.lng) && { label: 'Google Maps', icon: Navigation, onClick: () => window.open(`https://www.google.com/maps/search/?api=1&query=${place.lat},${place.lng}`, '_blank') },
                   { divider: true },
-                  onDeletePlace && { label: t('common.delete'), icon: Trash2, danger: true, onClick: () => onDeletePlace(place.id) },
+                  canEditPlaces && { label: t('common.delete'), icon: Trash2, danger: true, onClick: () => onDeletePlace(place.id) },
                 ])}
                 style={{
                   display: 'flex', alignItems: 'center', gap: 10,

client/src/components/Trips/TripMembersModal.tsx

@@ -3,6 +3,8 @@ import Modal from '../shared/Modal'
 import { tripsApi, authApi, shareApi } from '../../api/client'
 import { useToast } from '../shared/Toast'
 import { useAuthStore } from '../../store/authStore'
+import { useCanDo } from '../../store/permissionsStore'
+import { useTripStore } from '../../store/tripStore'
 import { Crown, UserMinus, UserPlus, Users, LogOut, Link2, Trash2, Copy, Check } from 'lucide-react'
 import { useTranslation } from '../../i18n'
 import { getApiErrorMessage } from '../../types'
@@ -32,7 +34,7 @@ function Avatar({ username, avatarUrl, size = 32 }: AvatarProps) {
   )
 }
 
-function ShareLinkSection({ tripId, t }: { tripId: number; t: any }) {
+function ShareLinkSection({ tripId, t }: { tripId: number; t: (key: string, params?: Record<string, string | number>) => string }) {
   const [shareToken, setShareToken] = useState<string | null>(null)
   const [loading, setLoading] = useState(true)
   const [copied, setCopied] = useState(false)
@@ -172,6 +174,10 @@ export default function TripMembersModal({ isOpen, onClose, tripId, tripTitle }:
   const toast = useToast()
   const { user } = useAuthStore()
   const { t } = useTranslation()
+  const can = useCanDo()
+  const trip = useTripStore((s) => s.trip)
+  const canManageMembers = can('member_manage', trip)
+  const canManageShare = can('share_manage', trip)
 
   useEffect(() => {
     if (isOpen && tripId) {
@@ -260,7 +266,7 @@ export default function TripMembersModal({ isOpen, onClose, tripId, tripTitle }:
         </div>
 
         {/* Add member dropdown */}
-        <div>
+        {canManageMembers && <div>
           <label style={{ display: 'block', fontSize: 12, fontWeight: 600, color: 'var(--text-secondary)', marginBottom: 8 }}>
             {t('members.inviteUser')}
           </label>
@@ -293,10 +299,10 @@ export default function TripMembersModal({ isOpen, onClose, tripId, tripTitle }:
               <UserPlus size={13} /> {adding ? '…' : t('members.invite')}
             </button>
           </div>
-          {availableUsers.length === 0 && allUsers.length > 0 && (
+          {availableUsers.length === 0 && allUsers.length > 0 && canManageMembers && (
             <p style={{ fontSize: 11.5, color: 'var(--text-faint)', margin: '6px 0 0' }}>{t('members.allHaveAccess')}</p>
           )}
-        </div>
+        </div>}
 
         {/* Members list */}
         <div>
@@ -317,7 +323,7 @@ export default function TripMembersModal({ isOpen, onClose, tripId, tripTitle }:
             <div style={{ display: 'flex', flexDirection: 'column', gap: 6 }}>
               {allMembers.map(member => {
                 const isSelf = member.id === user?.id
-                const canRemove = isCurrentOwner ? member.role !== 'owner' : isSelf
+                const canRemove = isSelf || (canManageMembers && (isCurrentOwner ? member.role !== 'owner' : false))
                 return (
                   <div key={member.id} style={{
                     display: 'flex', alignItems: 'center', gap: 10,
@@ -358,9 +364,9 @@ export default function TripMembersModal({ isOpen, onClose, tripId, tripTitle }:
         </div>
 
         {/* Right column: Share Link */}
-        <div style={{ borderLeft: '1px solid var(--border-faint)', paddingLeft: 24 }}>
+        {canManageShare && <div style={{ borderLeft: '1px solid var(--border-faint)', paddingLeft: 24 }}>
         <ShareLinkSection tripId={tripId} t={t} />
-        </div>
+        </div>}
 
         <style>{`@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:0.5} }`}</style>
       </div>