收紧剪贴板写入文本边界

让 Expo 和 Tauri 壳在写系统剪贴板前按共享上限截断文本

增加移动壳剪贴板写入边界测试和两端配置门禁

补充宿主壳协议文档和共享决策记录

apps/mobile-shell/scripts/check-config.mjs

@@ -1494,6 +1494,16 @@ for (const snippet of [
     throw new Error(`mobile shell HostBridge missing ${snippet}`);
   }
 }
+if (
+  !hostBridgeSource.includes(
+    'const clipboardText = normalizeHostBridgeClipboardText(',
+  ) ||
+  !hostBridgeSource.includes('Clipboard.setStringAsync(clipboardText.text)')
+) {
+  throw new Error(
+    'mobile shell clipboard.writeText must normalize text with the shared HostBridge clipboard boundary',
+  );
+}
 
 for (const snippet of [
   'CameraView',