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/res/xml/file_paths.xml

@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <paths>
+    <external-path name="external_storage" path="." />
     <external-files-path name="external_files" path="." />
     <files-path name="internal_files" path="." />
 </paths>