feat: complete offline write support with mutation queue + runtime SW cache config

- Add offline CRUD to todoRepo, budgetRepo, reservationRepo, accommodationRepo,
  dayRepo, tripRepo, fileRepo with optimistic Dexie writes and mutation queue
- Wire all store slices (todo, budget, reservations, files, dayNotes, assignments,
  tripStore) through repos for offline-aware writes
- Cover archive/unarchive, file toggleStar/update/delete, assignment create/delete,
  day title/notes update offline paths
- Migrate service worker from generateSW to injectManifest (custom sw.ts) with
  runtime-configurable api-data (7d/500) and map-tiles (30d/1000) cache policies
- Add Settings → Offline cache configuration UI with save/reset and live SW postMessage
- Extend mutationQueue flush to cover all writable Dexie tables

client/src/repo/fileRepo.ts

@@ -1,5 +1,6 @@
 import { filesApi } from '../api/client'
 import { offlineDb, upsertTripFiles } from '../db/offlineDb'
+import { mutationQueue, generateUUID } from '../sync/mutationQueue'
 import type { TripFile } from '../types'
 
 export const fileRepo = {
@@ -15,4 +16,61 @@ export const fileRepo = {
     upsertTripFiles(result.files)
     return result
   },
+
+  async update(tripId: number | string, id: number, data: Record<string, unknown>): Promise<unknown> {
+    if (!navigator.onLine) {
+      const existing = await offlineDb.tripFiles.get(id)
+      if (existing) await offlineDb.tripFiles.put({ ...existing, ...(data as Partial<TripFile>) })
+      await mutationQueue.enqueue({
+        id: generateUUID(),
+        tripId: Number(tripId),
+        method: 'PUT',
+        url: `/trips/${tripId}/files/${id}`,
+        body: data,
+        resource: 'tripFiles',
+      })
+      return { success: true }
+    }
+    const result = await filesApi.update(tripId, id, data)
+    const file = (result as { file?: TripFile }).file
+    if (file) offlineDb.tripFiles.put(file)
+    return result
+  },
+
+  async toggleStar(tripId: number | string, id: number): Promise<unknown> {
+    if (!navigator.onLine) {
+      const existing = await offlineDb.tripFiles.get(id)
+      if (existing) {
+        await offlineDb.tripFiles.put({ ...existing, starred: existing.starred ? 0 : 1 })
+      }
+      await mutationQueue.enqueue({
+        id: generateUUID(),
+        tripId: Number(tripId),
+        method: 'PATCH',
+        url: `/trips/${tripId}/files/${id}/star`,
+        body: undefined,
+      })
+      return { success: true }
+    }
+    return filesApi.toggleStar(tripId, id)
+  },
+
+  async delete(tripId: number | string, id: number): Promise<unknown> {
+    if (!navigator.onLine) {
+      await offlineDb.tripFiles.delete(id)
+      await mutationQueue.enqueue({
+        id: generateUUID(),
+        tripId: Number(tripId),
+        method: 'DELETE',
+        url: `/trips/${tripId}/files/${id}`,
+        body: undefined,
+        resource: 'tripFiles',
+        entityId: id,
+      })
+      return { success: true }
+    }
+    const result = await filesApi.delete(tripId, id)
+    offlineDb.tripFiles.delete(id)
+    return result
+  },
 }