feat(app-shell): 桌面端集成自动更新（electron-updater）

- 集成 electron-updater：检查更新/下载/安装/忽略此版本，并推送下载进度到前端

- 打包版启动后自动检查更新；托盘菜单支持手动检查

- preload 暴露 updater IPC + __brand 标记；前端新增更新弹窗与设置页版本/检查更新入口

- 补全发布配置：artifactName/publish；release workflow 增加上传 latest.yml

desktop/package.json

@@ -9,11 +9,15 @@
     "build:ui": "pushd ..\\\\frontend && npm run generate && popd && node scripts\\\\copy-ui.cjs",
     "build:backend": "uv sync --extra build && node scripts/build-backend.cjs",
     "build:icon": "node scripts/build-icon.cjs",
-    "dist": "npm run build:ui && npm run build:backend && npm run build:icon && electron-builder --win --x64"
+    "dist": "npm run build:ui && npm run build:backend && npm run build:icon && electron-builder --win --x64 --publish never"
+  },
+  "dependencies": {
+    "electron-updater": "^6.7.3"
   },
   "build": {
     "appId": "com.lifearchive.wechatdataanalysis",
     "productName": "WeChatDataAnalysis",
+    "artifactName": "${productName}-${version}-Setup.${ext}",
     "icon": "build/icon.ico",
     "asar": true,
     "directories": {
@@ -39,6 +43,12 @@
         "nsis"
       ]
     },
+    "publish": {
+      "provider": "github",
+      "owner": "LifeArchiveProject",
+      "repo": "WeChatDataAnalysis",
+      "releaseType": "release"
+    },
     "nsis": {
       "oneClick": false,
       "allowToChangeInstallationDirectory": true,