fix(conversation): 修复实时会话 TTS/回复被离屏 WS 抢占

- 列表预热仅预取消息缓存，避免后台 WebSocket 覆盖服务端连接
- RealtimeSession UI 回调按 owner 独占，防止 offscreen 覆盖聊天页
- 列表页聚焦时再 prewarm，会话页 TTS 入队优先 base64
- 管线下发 TTS 同时带 audio_base64 与 audio_url；协议说明同步
- 移除 TTS 排查用前后端调试日志，保留错误/告警
- 补充 WS / RealtimeSession / entry-warmup / 播放器相关单测

Co-authored-by: Cursor <cursoragent@cursor.com>

app-expo/src/core/settings/app-settings.ts

@@ -14,6 +14,7 @@ const KEY_LANGUAGE = 'app_settings_language';
 const KEY_LARGE_TEXT = 'app_settings_large_text';
 const KEY_DARK_MODE = 'app_settings_dark_mode';
 const KEY_THEME_NAME = 'app_settings_theme_name';
+const KEY_TTS_SPEAK_DEFAULT = 'app_settings_tts_speak_default';
 
 const webFallback: Record<string, string> = {};
 
@@ -83,5 +84,16 @@ export async function setThemeName(value: ThemeName): Promise<void> {
   await setStored(KEY_THEME_NAME, value);
 }
 
+/** 会话页「Speak / 本轮朗读」开关是否默认开启（跨会话记忆） */
+export async function getTtsSpeakDefault(): Promise<boolean> {
+  const v = await getStored(KEY_TTS_SPEAK_DEFAULT);
+  if (v == null || v === '') return false;
+  return v === 'true';
+}
+
+export async function setTtsSpeakDefault(value: boolean): Promise<void> {
+  await setStored(KEY_TTS_SPEAK_DEFAULT, value ? 'true' : 'false');
+}
+
 export { supportedLanguages, THEME_NAMES };
 export type { AppLanguage, ThemeName };