feat(subtitles): improve mpv hovered-token highlighting flow

- add subtitleStyle.hoverTokenColor config default + validation

- normalize hover color payloads and propagate configured color to mpv runtime

- refresh invisible overlay tokenization with current subtitle text and tighten hover overlay cleanup hooks

- record TASK-98 and subagent coordination updates

src/main.ts

@@ -654,6 +654,7 @@ const applyHoveredTokenOverlay = createApplyHoveredTokenOverlayHandler({
   getCurrentSubtitleData: () => appState.currentSubtitleData,
   getHoveredTokenIndex: () => appState.hoveredSubtitleTokenIndex,
   getHoveredSubtitleRevision: () => appState.hoveredSubtitleRevision,
+  getHoverTokenColor: () => getResolvedConfig().subtitleStyle.hoverTokenColor ?? null,
 });
 const buildImmersionMediaRuntimeMainDepsHandler = createBuildImmersionMediaRuntimeMainDepsHandler({
   getResolvedConfig: () => getResolvedConfig(),
@@ -2973,7 +2974,7 @@ function setVisibleOverlayVisible(visible: boolean): void {
 function setInvisibleOverlayVisible(visible: boolean): void {
   setInvisibleOverlayVisibleHandler(visible);
   if (visible) {
-    subtitleProcessingController.refreshCurrentSubtitle();
+    subtitleProcessingController.refreshCurrentSubtitle(appState.currentSubText);
   }
 }