fix(perf): stop reporting an unmeasured decoder as Software

lib/mpv/player/platform/player_tizen.dart

@@ -315,7 +315,6 @@ class PlayerTizen extends PlayerBase with VideoRectSupport {
     'videoWidth': _width,
     'videoHeight': _height,
     'playerType': 'tizen',
-    'videoDecoder': 'unknown',
   };
   @override
   Future<String?> getProperty(String name) async => switch (name) {

lib/widgets/video_controls/widgets/performance_overlay/performance_overlay.dart

@@ -68,6 +68,10 @@ class _PlayerPerformanceOverlayState extends State<PlayerPerformanceOverlay> {
   @override
   Widget build(BuildContext context) {
     final isMpv = _stats.playerType == 'mpv';
+    // `!isMpv` used to mean ExoPlayer, back when those were the only two
+    // backends. Tizen is a third, and these metrics are ExoPlayer's alone, so
+    // ask for it by name rather than by elimination.
+    final isExo = _stats.playerType == 'exoplayer';
 
     final sections = <Widget>[
       _buildSection(Symbols.videocam_rounded, t.fileInfo.video, [
@@ -76,8 +80,8 @@ class _PlayerPerformanceOverlayState extends State<PlayerPerformanceOverlay> {
         if (_stats.hasValidVideoFps) _metric(t.performanceOverlay.fps, _stats.videoFpsFormatted),
         if (_stats.hasValidVideoBitrate) _metric(t.fileInfo.bitrate, _stats.videoBitrateFormatted),
         _metric(t.performanceOverlay.decoder, _stats.hwdecFormatted),
-        if (!isMpv && _stats.videoDecoderName != null) _metric(t.performanceOverlay.rawDecoder, _stats.videoDecoderRaw),
-        if (!isMpv) _metric(t.performanceOverlay.tunneling, _stats.tunneledPlaybackFormatted),
+        if (isExo && _stats.videoDecoderName != null) _metric(t.performanceOverlay.rawDecoder, _stats.videoDecoderRaw),
+        if (isExo) _metric(t.performanceOverlay.tunneling, _stats.tunneledPlaybackFormatted),
         if (_stats.aspectName != null && _stats.aspectName!.isNotEmpty)
           _metric(t.performanceOverlay.aspect, _stats.aspectName!),
         if (_stats.rotate != null && _stats.rotate != 0) _metric(t.performanceOverlay.rotation, _stats.rotateFormatted),
@@ -91,7 +95,7 @@ class _PlayerPerformanceOverlayState extends State<PlayerPerformanceOverlay> {
         _metric(t.performanceOverlay.sampleRate, _stats.sampleRateFormatted),
         _metric(t.fileInfo.channels, _stats.audioChannels ?? t.common.notAvailable),
         if (_stats.hasValidAudioBitrate) _metric(t.fileInfo.bitrate, _stats.audioBitrateFormatted),
-        if (!isMpv && _stats.audioDecoderName != null)
+        if (isExo && _stats.audioDecoderName != null)
           _metric(t.performanceOverlay.decoder, _stats.audioDecoderFormatted),
       ]),
       if (isMpv)

lib/widgets/video_controls/widgets/performance_overlay/performance_stats.dart

@@ -259,10 +259,13 @@ class PerformanceStats {
       }
       return t.performanceOverlay.decoderSoftware;
     }
-    // For MPV, use hwdec-current property
-    if (hwdecCurrent == null || hwdecCurrent!.isEmpty || hwdecCurrent == 'no') {
-      return t.performanceOverlay.decoderSoftware;
-    }
+    // For MPV, use hwdec-current property. Only mpv's own `no` is evidence of
+    // software decoding; an absent or empty value means the backend never told
+    // us, which is not the same claim. Backends that decode outside the app
+    // (Tizen's Capi plane) never report one, and asserting "Software" there is
+    // the exact error ACCEPTANCE.md forbids in the other direction.
+    if (hwdecCurrent == 'no') return t.performanceOverlay.decoderSoftware;
+    if (hwdecCurrent == null || hwdecCurrent!.isEmpty) return t.common.notAvailable;
     return hwdecCurrent!;
   }
 
@@ -372,6 +375,7 @@ class PerformanceStats {
     return switch (playerType.toLowerCase()) {
       'mpv' => 'MPV',
       'exoplayer' => 'ExoPlayer',
+      'tizen' => 'Tizen',
       _ => playerType,
     };
   }

lib/widgets/video_controls/widgets/performance_overlay/performance_stats_service.dart

@@ -196,6 +196,21 @@ class PerformanceStatsService {
         uiFps: _currentUiFps,
       );
       _emit(stats);
+    } else if (playerType == 'tizen') {
+      // The Capi backend decodes on the TV's own SoC, outside Flutter, and
+      // exposes no decoder name, hwdec state or frame counters. Report only
+      // what it actually returns; every other metric stays null so the
+      // overlay prints N/A rather than inventing a value. Without this branch
+      // Tizen fell through to the ExoPlayer parse below, which labelled the
+      // backend "ExoPlayer" and left hwdec null - read as "Software".
+      final stats = PerformanceStats(
+        playerType: 'tizen',
+        videoWidth: statsMap['videoWidth'] as int?,
+        videoHeight: statsMap['videoHeight'] as int?,
+        appMemoryBytes: appMemory,
+        uiFps: _currentUiFps,
+      );
+      _emit(stats);
     } else {
       // Parse ExoPlayer stats format
       final stats = PerformanceStats(

test/widgets/performance_stats_service_test.dart

@@ -1,6 +1,7 @@
 import 'dart:async';
 
 import 'package:flutter_test/flutter_test.dart';
+import 'package:plezy/i18n/strings.g.dart';
 import 'package:plezy/mpv/mpv.dart';
 import 'package:plezy/widgets/video_controls/widgets/performance_overlay/performance_stats.dart';
 import 'package:plezy/widgets/video_controls/widgets/performance_overlay/performance_stats_service.dart';
@@ -292,4 +293,31 @@ void main() {
       expect(stats.droppedFramesFormatted, '3');
     });
   });
+
+  group('a backend that decodes outside the app', () {
+    test('Tizen reports itself, not ExoPlayer', () async {
+      final stats = await _firstStats(
+        _NativeStatsPlayer({'playerType': 'tizen', 'videoWidth': 1920, 'videoHeight': 1080}),
+      );
+
+      expect(stats.playerType, 'tizen');
+      expect(stats.playerTypeFormatted, 'Tizen');
+      expect(stats.videoWidth, 1920);
+      // Falling through to the ExoPlayer parse used to invent these.
+      expect(stats.videoDecoderName, isNull);
+    });
+
+    test('no hwdec signal reads as unavailable, never as software', () {
+      // The Capi plane exposes no hwdec state. Claiming software decoding
+      // there asserts a measurement nobody took.
+      const stats = PerformanceStats(playerType: 'tizen');
+      expect(stats.hwdecFormatted, isNot(t.performanceOverlay.decoderSoftware));
+      expect(stats.hwdecFormatted, t.common.notAvailable);
+    });
+
+    test("mpv's own 'no' is still real evidence of software decoding", () {
+      const stats = PerformanceStats(playerType: 'mpv', hwdecCurrent: 'no');
+      expect(stats.hwdecFormatted, t.performanceOverlay.decoderSoftware);
+    });
+  });
 }