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>

app/src/main/kotlin/com/syncflow/data/db/SyncDatabase.kt

@@ -15,20 +15,27 @@ import com.syncflow.data.db.entities.*
         SyncConflictEntity::class,
         SyncEventEntity::class,
     ],
-    version = 3,
+    version = 4,
     exportSchema = true,
 )
 @TypeConverters(DbConverters::class)
 abstract class SyncDatabase : RoomDatabase() {
 
     companion object {
-        // Wipe file states: timestamps were stored as epoch-seconds, now epoch-millis.
-        // All previously saved states are wrong so we drop and re-learn on next sync.
         val MIGRATION_2_3 = object : Migration(2, 3) {
             override fun migrate(db: SupportSQLiteDatabase) {
                 db.execSQL("DELETE FROM sync_file_states")
             }
         }
+
+        val MIGRATION_3_4 = object : Migration(3, 4) {
+            override fun migrate(db: SupportSQLiteDatabase) {
+                db.execSQL("ALTER TABLE sync_pairs ADD COLUMN lastSyncUploaded INTEGER NOT NULL DEFAULT 0")
+                db.execSQL("ALTER TABLE sync_pairs ADD COLUMN lastSyncDownloaded INTEGER NOT NULL DEFAULT 0")
+                db.execSQL("ALTER TABLE sync_pairs ADD COLUMN lastSyncDeleted INTEGER NOT NULL DEFAULT 0")
+                db.execSQL("ALTER TABLE sync_pairs ADD COLUMN lastSyncBytesTransferred INTEGER NOT NULL DEFAULT 0")
+            }
+        }
     }
     abstract fun cloudAccountDao(): CloudAccountDao
     abstract fun syncPairDao(): SyncPairDao