v1.0.23: functional Files tab, background service persistence, startup indexer, curved icon

- FilesScreen: per-file context menu (Open, Share, Rename, Delete), rename dialog,
  delete confirmation, FileProvider-based open/share intents, Snackbar error feedback
- FilesViewModel: FileAction sealed class + SharedFlow; openFile, shareFile,
  deleteFile, renameFile with DB cleanup; resolveFile handles SAF primary: URIs
- FileWatchService: stopWithTask=false keeps watcher alive after app swipe-away;
  catchupScan on startup detects changes missed while service was not running;
  SyncFileStateDao injected; FileObserver used for real-path SAF URIs
- BootReceiver: handles MY_PACKAGE_REPLACED to restart service after app update
- file_paths.xml: added external-path so FileProvider can serve /storage/emulated/0 files
- ic_launcher_foreground: three curved stroke-based arrows (quadratic bezier, round caps)

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

app/src/main/kotlin/com/syncflow/worker/FileWatchService.kt

@@ -16,6 +16,7 @@ import androidx.work.ExistingWorkPolicy
 import androidx.work.WorkManager
 import com.syncflow.MainActivity
 import com.syncflow.R
+import com.syncflow.data.db.SyncFileStateDao
 import com.syncflow.data.db.SyncPairDao
 import com.syncflow.domain.model.ScheduleType
 import dagger.hilt.android.AndroidEntryPoint
@@ -28,6 +29,7 @@ import javax.inject.Inject
 class FileWatchService : Service() {
 
     @Inject lateinit var syncPairDao: SyncPairDao
+    @Inject lateinit var fileStateDao: SyncFileStateDao
 
     private val scope = CoroutineScope(Dispatchers.IO + SupervisorJob())
     private val mainHandler = Handler(Looper.getMainLooper())
@@ -151,6 +153,36 @@ class FileWatchService : Service() {
         observer.startWatching()
         fileObservers[pairId] = observer
         Timber.d("FileWatchService: watching filesystem path for pair $pairId: $path")
+        // Check if anything changed while the service was not running
+        scope.launch { catchupScan(pairId, dir, wifiOnly, chargingOnly) }
+    }
+
+    private suspend fun catchupScan(pairId: Long, dir: File, wifiOnly: Boolean, chargingOnly: Boolean) {
+        val known = fileStateDao.getForPair(pairId).associateBy { it.relativePath }
+        if (known.isEmpty()) return // Never synced — first sync will be triggered manually
+
+        val current = mutableMapOf<String, Long>()
+        dir.walk().filter { it.isFile }.forEach { f ->
+            current[f.relativeTo(dir).path.replace('\\', '/')] = f.lastModified()
+        }
+
+        val hasNew      = current.any { (rel, _) -> rel !in known }
+        val hasModified = current.any { (rel, mtime) ->
+            val s = known[rel]; s != null && s.localModifiedAt != null &&
+            s.localModifiedAt.toEpochMilli() != mtime
+        }
+        val hasDeleted  = known.keys.any { rel -> rel !in current }
+
+        if (hasNew || hasModified || hasDeleted) {
+            Timber.d("FileWatchService: catchup detected changes for pair $pairId, scheduling sync")
+            val pair = syncPairDao.getById(pairId) ?: return
+            WorkManager.getInstance(applicationContext)
+                .enqueueUniqueWork(
+                    "catchup_$pairId",
+                    ExistingWorkPolicy.KEEP,
+                    SyncWorker.buildOneTimeRequest(pairId, wifiOnly, chargingOnly),
+                )
+        }
     }
 
     private fun onChangeDetected(pairId: Long, wifiOnly: Boolean, chargingOnly: Boolean) {