fix(player): 记住拖动后的实际播放位置

test/player/player_logic_test.dart

@@ -218,6 +218,75 @@ void main() {
       logic.dispose();
       await _drain(logic);
     });
+
+    testWidgets(
+      'should_cache_actual_position_after_seek_completes',
+      (tester) async {
+        late BuildContext context;
+        await tester.pumpWidget(
+          MaterialApp(
+            home: Builder(
+              builder: (pageContext) {
+                context = pageContext;
+                return const Scaffold(body: SizedBox.expand());
+              },
+            ),
+          ),
+        );
+        final cache = PlaybackPositionCache();
+        final history = FakeWatchHistory();
+        final factory = _VideoRecordingFactory();
+        late PlayerLogic logic;
+        await tester.runAsync(() async {
+          logic = _logic(history, positionCache: cache);
+          logic.attach(
+            PlayerPage(drama: _drama('signal'), initialIndex: 0),
+            isMounted: () => true,
+          );
+          logic.start(
+            factory: factory.create,
+            coordinator: PlaybackCoordinator(),
+          );
+          await _drain(logic);
+        });
+        final player = logic.session.active! as _VideoRecordingPlayer;
+        logic.beginScrub(player);
+
+        await tester.runAsync(
+          () => logic.seekTo(
+            context,
+            player,
+            const Duration(seconds: 42),
+          ),
+        );
+        await tester.runAsync(() => logic.pendingWrite);
+
+        expect(
+          cache.read('signal-1', dramaId: 'signal')?.position,
+          const Duration(seconds: 42),
+        );
+        expect(history.writes.last, 'signal-1|42000|false');
+
+        logic.beginScrub(player);
+        await tester.runAsync(
+          () => logic.seekTo(
+            context,
+            player,
+            const Duration(minutes: 2),
+          ),
+        );
+        await tester.runAsync(() => logic.pendingWrite);
+
+        expect(player.controller.value.position, const Duration(minutes: 1));
+        expect(
+          cache.read('signal-1', dramaId: 'signal')?.position,
+          const Duration(minutes: 1),
+        );
+        expect(history.writes.last, 'signal-1|60000|false');
+        logic.dispose();
+        await tester.pump();
+      },
+    );
   });
 
   test('should_play_local_file_without_ticket_when_episode_is_downloaded',
@@ -1257,6 +1326,18 @@ class _VideoRecordingPlayer extends VideoPlayerPort {
   @override
   Future<void> pause() async {}
 
+  @override
+  Future<void> seekTo(Duration position) async {
+    final current = controller.value;
+    controller.value = VideoPlayerValue(
+      duration: current.duration,
+      size: current.size,
+      position: position,
+      isInitialized: current.isInitialized,
+      isPlaying: current.isPlaying,
+    );
+  }
+
   @override
   Future<void> dispose() async {
     if (disposed) return;