guide层v1: 全局向导交互层落地(状态签名earcon/turn cue/静默看门狗/纠错) + 6游戏接线 + 8句向导语音 + 测试全绿

- engine/guide.js 运行时合成8个签名earcon(方法论L2硬参数)，off档零定时器，插播queue不顶对白
- settings: guide三档(full/standard/off默认full) + 语速2.2视障档；audio: isVoicePlaying()/setRateBoostEnabled() 清两个已知问题
- 6游戏按schemes§2接线: storyline看门狗+无效手势纠错、simon免扣重听看门狗、escape turn cue+提前卡关提示、rhythm gd_answer/gd_miss+结算看门狗+快进豁免、space首撞指令提示+结算看门狗、rpg格挡纠错+60s催促+状态签名
- 大厅设置面板+向导文档(14-guide-layer.md)+00-global-ux §6；R5台词表补4条一致性
- 试玩转写含向导事件；6 playtest(guide=off断言零改动)+guide.test(34断言)+资产终检全绿

web/rhythm/test/playtest.mjs

@@ -153,7 +153,7 @@ let audio = null; let game = null; let playLog = []; let gestures = 0;
 async function newWorld(progress = null) {
   store.clear();
   if (progress) store.set(PROGRESS_KEY, JSON.stringify(progress));
-  settings.set({ voice: 'female', speed: 1.0, bgm: 1.0 });
+  settings.set({ guide: 'off', voice: 'female', speed: 1.0, bgm: 1.0 });
   nowMs = 0; timers.clear(); vibLog.length = 0; srcLog.length = 0; fetchLog.length = 0; blocked.length = 0;
   audio = new WebAudioEngine('audio/');
   playLog = [];