fix: prevent IDB write-stall from blocking trip page and sync loop

clearAll() now clears all tables in a transaction instead of calling
offlineDb.delete(), which triggered our versionchange handler and put
Dexie into a broken write state for the rest of the session.

tripRepo.get() gets the same 2 s timeout guard as list() so a stalled
IDB read no longer freezes the trip splash screen.

_doSync wraps each syncTrip() in a 30 s per-trip timeout so a single
stalled write transaction cannot prevent the loop from advancing to
subsequent trips.

client/src/db/offlineDb.ts

@@ -199,7 +199,46 @@ export async function clearBlobCache(): Promise<void> {
 
 /** Wipe the entire offline database (called on logout). */
 export async function clearAll(): Promise<void> {
-  await offlineDb.delete();
-  // Re-open so subsequent operations don't fail
-  await offlineDb.open();
+  // Use table.clear() instead of offlineDb.delete() to avoid triggering the
+  // versionchange handler (which calls close()), which would put Dexie into a
+  // broken write state for the remainder of the session.
+  await offlineDb.transaction(
+    'rw',
+    [
+      offlineDb.trips,
+      offlineDb.days,
+      offlineDb.places,
+      offlineDb.packingItems,
+      offlineDb.todoItems,
+      offlineDb.budgetItems,
+      offlineDb.reservations,
+      offlineDb.tripFiles,
+      offlineDb.accommodations,
+      offlineDb.tripMembers,
+      offlineDb.tags,
+      offlineDb.categories,
+      offlineDb.mutationQueue,
+      offlineDb.syncMeta,
+      offlineDb.blobCache,
+    ],
+    async () => {
+      await Promise.all([
+        offlineDb.trips.clear(),
+        offlineDb.days.clear(),
+        offlineDb.places.clear(),
+        offlineDb.packingItems.clear(),
+        offlineDb.todoItems.clear(),
+        offlineDb.budgetItems.clear(),
+        offlineDb.reservations.clear(),
+        offlineDb.tripFiles.clear(),
+        offlineDb.accommodations.clear(),
+        offlineDb.tripMembers.clear(),
+        offlineDb.tags.clear(),
+        offlineDb.categories.clear(),
+        offlineDb.mutationQueue.clear(),
+        offlineDb.syncMeta.clear(),
+        offlineDb.blobCache.clear(),
+      ])
+    },
+  )
 }

client/src/repo/tripRepo.ts

@@ -48,7 +48,10 @@ export const tripRepo = {
   },
 
   async get(tripId: number | string): Promise<{ trip: Trip; refresh: TripRefresh }> {
-    const cached = await offlineDb.trips.get(Number(tripId))
+    const cached = await Promise.race([
+      offlineDb.trips.get(Number(tripId)).catch(() => undefined),
+      new Promise<undefined>(resolve => setTimeout(() => resolve(undefined), 2000)),
+    ])
 
     const refresh: TripRefresh = (async () => {
       try {

client/src/sync/tripSyncManager.ts

@@ -195,7 +195,12 @@ export const tripSyncManager = {
       onProgress?.({ phase: 'trip', tripId: trip.id, index: i, total: toSync.length })
       let tripOk = false
       try {
-        await syncTrip(trip.id)
+        await Promise.race([
+          syncTrip(trip.id),
+          new Promise<never>((_, reject) =>
+            setTimeout(() => reject(new Error('syncTrip timeout')), 30_000)
+          ),
+        ])
         tripOk = true
       } catch (err) {
         if (isQuotaError(err)) {