feat(config): unify mpv plugin options under main config and add CSS/Ani

- Replace subminer.conf plugin config with mpv.* fields in config.jsonc
- Add socketPath, backend, autoStartSubMiner, pauseUntilOverlayReady, aniskipEnabled/buttonKey, subminerBinaryPath to mpv config
- Add subtitleSidebar.css field; migrate legacy sidebar appearance fields
- Add paintOrder and WebkitTextStroke to subtitle style options
- Update default subtitle/sidebar fontFamily to CJK-first stack
- Fix overlay visible state surviving mpv y-r restart
- Fix live config saves applying subtitle CSS immediately to open overlays
- Migrate legacy primary/secondary subtitle appearance into subtitleStyle.css on load
- Switch AniSkip button key setting to click-to-learn key capture

src/main/runtime/mpv-main-event-bindings.test.ts

@@ -95,3 +95,66 @@ test('main mpv event binder wires callbacks through to runtime deps', () => {
   assert.ok(calls.includes('sync-immersion'));
   assert.ok(calls.includes('flush-playback'));
 });
+
+test('main mpv event binder runs mpv-connected callback on connection', () => {
+  const handlers = new Map<string, (payload: unknown) => void>();
+  const calls: string[] = [];
+
+  const bind = createBindMpvMainEventHandlersHandler({
+    reportJellyfinRemoteStopped: () => calls.push('remote-stopped'),
+    syncOverlayMpvSubtitleSuppression: () => calls.push('sync-overlay-mpv-sub'),
+    onMpvConnected: () => calls.push('mpv-connected'),
+    resetSubtitleSidebarEmbeddedLayout: () => calls.push('reset-sidebar-layout'),
+    hasInitialPlaybackQuitOnDisconnectArg: () => false,
+    isOverlayRuntimeInitialized: () => false,
+    shouldQuitOnDisconnectWhenOverlayRuntimeInitialized: () => false,
+    isQuitOnDisconnectArmed: () => false,
+    scheduleQuitCheck: () => {},
+    isMpvConnected: () => true,
+    quitApp: () => {},
+
+    recordImmersionSubtitleLine: () => {},
+    hasSubtitleTimingTracker: () => false,
+    recordSubtitleTiming: () => {},
+    maybeRunAnilistPostWatchUpdate: async () => {},
+    logSubtitleTimingError: () => {},
+    setCurrentSubText: () => {},
+    broadcastSubtitle: () => {},
+    onSubtitleChange: () => {},
+    refreshDiscordPresence: () => calls.push('presence-refresh'),
+
+    setCurrentSubAssText: () => {},
+    broadcastSubtitleAss: () => {},
+    broadcastSecondarySubtitle: () => {},
+
+    updateCurrentMediaPath: () => {},
+    restoreMpvSubVisibility: () => {},
+    getCurrentAnilistMediaKey: () => null,
+    resetAnilistMediaTracking: () => {},
+    maybeProbeAnilistDuration: () => {},
+    ensureAnilistMediaGuess: () => {},
+    syncImmersionMediaState: () => {},
+
+    updateCurrentMediaTitle: () => {},
+    resetAnilistMediaGuessState: () => {},
+    notifyImmersionTitleUpdate: () => {},
+
+    recordPlaybackPosition: () => {},
+    recordMediaDuration: () => {},
+    reportJellyfinRemoteProgress: () => {},
+    recordPauseState: () => {},
+
+    updateSubtitleRenderMetrics: () => {},
+    setPreviousSecondarySubVisibility: () => {},
+  });
+
+  bind({
+    on: (event, handler) => {
+      handlers.set(event, handler as (payload: unknown) => void);
+    },
+  });
+
+  handlers.get('connection-change')?.({ connected: true });
+
+  assert.ok(calls.includes('mpv-connected'));
+});