fix: live tv dvr seek via keyboard/remote

close #789

lib/screens/video_player_screen.dart

@@ -1877,19 +1877,23 @@ class VideoPlayerScreenState extends State<VideoPlayerScreen> with WidgetsBindin
     receiver.onSeekForward = () async {
       if (player == null) return;
       final settings = await SettingsService.getInstance();
-      final target = clampSeekPosition(
-        player!,
-        player!.state.position + Duration(seconds: settings.getSeekTimeSmall()),
-      );
+      final seekSeconds = settings.getSeekTimeSmall();
+      if (widget.isLive && _captureBuffer != null) {
+        await _seekLivePosition(_currentPositionEpoch + seekSeconds);
+        return;
+      }
+      final target = clampSeekPosition(player!, player!.state.position + Duration(seconds: seekSeconds));
       await player!.seek(target);
     };
     receiver.onSeekBackward = () async {
       if (player == null) return;
       final settings = await SettingsService.getInstance();
-      final target = clampSeekPosition(
-        player!,
-        player!.state.position - Duration(seconds: settings.getSeekTimeSmall()),
-      );
+      final seekSeconds = settings.getSeekTimeSmall();
+      if (widget.isLive && _captureBuffer != null) {
+        await _seekLivePosition(_currentPositionEpoch - seekSeconds);
+        return;
+      }
+      final target = clampSeekPosition(player!, player!.state.position - Duration(seconds: seekSeconds));
       await player!.seek(target);
     };
     receiver.onVolumeUp = () async {

lib/services/keyboard_shortcuts_service.dart

@@ -139,6 +139,8 @@ class KeyboardShortcutsService {
     VoidCallback? onBack,
     VoidCallback? onToggleShader,
     VoidCallback? onSkipMarker,
+    int? currentPositionEpoch,
+    ValueChanged<int>? onLiveSeek,
   }) {
     if (event is! KeyDownEvent) return KeyEventResult.ignored;
 
@@ -216,6 +218,8 @@ class KeyboardShortcutsService {
           onPreviousChapter,
           onToggleShader: onToggleShader,
           onSkipMarker: onSkipMarker,
+          currentPositionEpoch: currentPositionEpoch,
+          onLiveSeek: onLiveSeek,
         );
         return KeyEventResult.handled;
       }
@@ -235,7 +239,18 @@ class KeyboardShortcutsService {
     VoidCallback? onPreviousChapter, {
     VoidCallback? onToggleShader,
     VoidCallback? onSkipMarker,
+    int? currentPositionEpoch,
+    ValueChanged<int>? onLiveSeek,
   }) {
+    void performSeek(int offsetSeconds) {
+      if (onLiveSeek != null && currentPositionEpoch != null) {
+        onLiveSeek(currentPositionEpoch + offsetSeconds);
+      } else {
+        final target = clampSeekPosition(player, player.state.position + Duration(seconds: offsetSeconds));
+        unawaited(player.seek(target));
+      }
+    }
+
     switch (action) {
       case 'play_pause':
         player.playOrPause();
@@ -251,20 +266,16 @@ class KeyboardShortcutsService {
         _settingsService.setVolume(newVolume);
         break;
       case 'seek_forward':
-        final fwdTarget = clampSeekPosition(player, player.state.position + Duration(seconds: _seekTimeSmall));
-        unawaited(player.seek(fwdTarget));
+        performSeek(_seekTimeSmall);
         break;
       case 'seek_backward':
-        final bwdTarget = clampSeekPosition(player, player.state.position - Duration(seconds: _seekTimeSmall));
-        unawaited(player.seek(bwdTarget));
+        performSeek(-_seekTimeSmall);
         break;
       case 'seek_forward_large':
-        final fwdLTarget = clampSeekPosition(player, player.state.position + Duration(seconds: _seekTimeLarge));
-        unawaited(player.seek(fwdLTarget));
+        performSeek(_seekTimeLarge);
         break;
       case 'seek_backward_large':
-        final bwdLTarget = clampSeekPosition(player, player.state.position - Duration(seconds: _seekTimeLarge));
-        unawaited(player.seek(bwdLTarget));
+        performSeek(-_seekTimeLarge);
         break;
       case 'fullscreen_toggle':
         onToggleFullscreen?.call();

lib/widgets/video_controls/video_controls.dart

@@ -1721,6 +1721,8 @@ class _PlexVideoControlsState extends State<PlexVideoControls> with WindowListen
         _previousChapter,
         onBack: widget.onBack ?? () => Navigator.of(context).pop(true),
         onToggleShader: _toggleShader,
+        currentPositionEpoch: widget.currentPositionEpoch,
+        onLiveSeek: widget.onLiveSeek,
       );
       if (result == KeyEventResult.handled) {
         _focusNode.requestFocus(); // self-heal focus
@@ -1951,6 +1953,8 @@ class _PlexVideoControlsState extends State<PlexVideoControls> with WindowListen
               onBack: widget.onBack ?? () => Navigator.of(context).pop(true),
               onToggleShader: _toggleShader,
               onSkipMarker: _performAutoSkip,
+              currentPositionEpoch: widget.currentPositionEpoch,
+              onLiveSeek: widget.onLiveSeek,
             );
             // Let non-navigation keys (volume, etc.) pass through to the OS
             if (!event.logicalKey.isNavigationKey) return KeyEventResult.ignored;