v1.0.63: live sync progress counters, pause/resume, .gitignore fix

- SyncEngine: accepts onProgress callback — emits uploaded/downloaded/
  deleted/bytes counts atomically as each file completes
- SyncWorker: streams progress to WorkManager data so the UI can poll
  it live; reports per-run counters in the completion notification;
  adds pause/resume support
- HomeViewModel/PairDetailViewModel: subscribe to live WorkManager
  progress and surface it via SyncProgress state
- SyncPairEntity/SyncPairDao/SyncDatabase: persist last-run counters
  (uploaded, downloaded, deleted, bytesTransferred) in the DB with a
  Room migration (v3→v4)
- AppModule: provides WorkManager as an injectable singleton
- .gitignore: add .kotlin/ to exclude compiler session files

Security: no new issues — all logging via Timber (debug-only), DB
queries use Room parameterized API, file sharing via FileProvider.

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

version.properties

@@ -1,2 +1,2 @@
-VERSION_NAME=1.0.59
-VERSION_CODE=60
+VERSION_NAME=1.0.63
+VERSION_CODE=64