feat(w3): add continuous read mode and Wave 3 plan

Introduce ReadModeOverlay with device width and font theme persistence, sidebar and volume menu entry, plus E2E-READ-01 through 03.

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

public/locales/en/translation.json

@@ -538,5 +538,17 @@
   "tts.started": "Reading aloud",
   "tts.stopped": "Stopped reading",
   "tts.noText": "Nothing to read",
-  "home.exportAllWave2": "Bulk export coming in a later release"
+  "home.exportAllWave2": "Bulk export coming in a later release",
+  "readMode.title": "Read mode",
+  "readMode.open": "Read mode",
+  "readMode.exit": "Exit reading",
+  "readMode.deviceWidth": "Device width",
+  "readMode.devicePhone": "Phone (360px)",
+  "readMode.deviceTablet": "Tablet (768px)",
+  "readMode.deviceDesktop": "Desktop (100%)",
+  "readMode.fontTheme": "Font theme",
+  "readMode.fontSerif": "Serif",
+  "readMode.fontSans": "Sans-serif",
+  "readMode.fontEyeCare": "Eye care",
+  "readMode.tts": "Read aloud"
 }

public/locales/zh-CN/translation.json

@@ -538,5 +538,17 @@
   "tts.started": "开始朗读",
   "tts.stopped": "已停止朗读",
   "tts.noText": "没有可朗读的内容",
-  "home.exportAllWave2": "批量导出将在后续版本提供"
+  "home.exportAllWave2": "批量导出将在后续版本提供",
+  "readMode.title": "阅读模式",
+  "readMode.open": "阅读模式",
+  "readMode.exit": "退出阅读",
+  "readMode.deviceWidth": "设备宽度",
+  "readMode.devicePhone": "手机 (360px)",
+  "readMode.deviceTablet": "平板 (768px)",
+  "readMode.deviceDesktop": "桌面 (100%)",
+  "readMode.fontTheme": "字体主题",
+  "readMode.fontSerif": "衬线",
+  "readMode.fontSans": "无衬线",
+  "readMode.fontEyeCare": "护眼",
+  "readMode.tts": "朗读"
 }