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

docs/subagents/agents/codex-mpv-plugin-hover-20260222T004010Z-b3k9.md

@@ -0,0 +1,14 @@
+# Agent: `codex-mpv-plugin-hover-20260222T004010Z-b3k9`
+
+- alias: `codex-mpv-plugin-hover`
+- mission: `Shift mpv subtitle token highlighting from overlay hack to plugin-driven subtitle color mutation`
+- status: `completed`
+- branch: `main`
+- started_at: `2026-02-22T00:40:10Z`
+- heartbeat_minutes: `5`
+
+## Current Work
+- [2026-02-22T01:22:00Z] implemented plugin-side hover handler in `plugin/subminer.lua`: parses `subminer-hover-token` payload, aligns tokens via startPos/endPos, renders highlighted subtitle via `mp.set_osd_ass`, and clears on invalid/revision-stale messages.
+- [2026-02-22T21:06:00Z] implemented plugin-directed payload path: Electron now sends `script-message-to yomipv yomipv-hover-token` JSON instead of osd-overlay ASS; added subtitle revision guard and hover payload metadata in runtime.
+- [2026-02-22T21:06:00Z] added `subtitle/hover_highlight.lua` module in Yomipv and wired init from `main.lua`.
+- [2026-02-22T21:06:00Z] added runtime tests for payload command generation and hover-clear behavior (`src/main/runtime/mpv-hover-highlight.test.ts`).