feat(config): auto-persist Video & Quality settings to config.json across app restarts

frontend/src/main.ts

@@ -420,6 +420,26 @@ function crfQualityHint(crf: number): string {
   return tr.crfHintSmall;
 }
 
+let saveCfgTimer = 0;
+function persistVideoSettings() {
+  const api = appApi();
+  if (!api || !state.appInfo) return;
+  state.appInfo.config.defaultEncoder = state.encoder;
+  state.appInfo.config.defaultHwDecode = state.hwDecode;
+  state.appInfo.config.defaultPreset = state.preset;
+  state.appInfo.config.defaultCrf = state.crf;
+  state.appInfo.config.defaultFps = state.fps;
+  state.appInfo.config.defaultTune = state.tune;
+  state.appInfo.config.defaultMergeAudio = state.audioMode === 'merge';
+
+  window.clearTimeout(saveCfgTimer);
+  saveCfgTimer = window.setTimeout(() => {
+    if (state.appInfo) {
+      void api.SaveConfig(state.appInfo.config);
+    }
+  }, 350);
+}
+
 function syncControlsFromState() {
   el<'select'>('encoderSelect').value = state.encoder;
   el<'select'>('hwDecodeSelect').value = state.hwDecode;
@@ -1168,26 +1188,32 @@ function bindEvents() {
   el<'select'>('encoderSelect').addEventListener('change', (e) => {
     state.encoder = (e.target as HTMLSelectElement).value;
     syncControlsFromState();
+    persistVideoSettings();
   });
   el<'select'>('hwDecodeSelect').addEventListener('change', (e) => {
     state.hwDecode = (e.target as HTMLSelectElement).value;
+    persistVideoSettings();
     void refreshCLI();
   });
   el<'input'>('crfRange').addEventListener('input', (e) => {
     state.crf = Number((e.target as HTMLInputElement).value);
     el<'span'>('crfLabel').textContent = `${state.crf} · ${crfQualityHint(state.crf)}`;
+    persistVideoSettings();
     void refreshCLI();
   });
   el<'select'>('presetSelect').addEventListener('change', (e) => {
     state.preset = (e.target as HTMLSelectElement).value;
+    persistVideoSettings();
     void refreshCLI();
   });
   el<'select'>('tuneSelect').addEventListener('change', (e) => {
     state.tune = (e.target as HTMLSelectElement).value;
+    persistVideoSettings();
     void refreshCLI();
   });
   el<'select'>('fpsSelect').addEventListener('change', (e) => {
     state.fps = Number((e.target as HTMLSelectElement).value);
+    persistVideoSettings();
     void refreshCLI();
   });
 
@@ -1206,6 +1232,7 @@ function bindEvents() {
     b.addEventListener('click', () => {
       state.audioMode = b.dataset.amode as 'merge' | 'track' | 'mute';
       syncControlsFromState();
+      persistVideoSettings();
     });
   });