feat: 添加 Tauri 自动更新器插件支持 (updater plugin)

- 添加 tauri-plugin-updater / tauri-plugin-process Rust 依赖
- 注册 updater 和 process 插件到 Tauri 构建器
- 配置 tauri.conf.json 更新器端点与公钥占位
- 添加 @tauri-apps/plugin-updater / plugin-process npm 依赖
- 创建 useUpdater composable（静默检查、手动检查、下载进度、安装重启）
- 在 AppLayout 标题栏集成更新交互 UI（下载按钮、进度条、安装状态）
- 添加 .pnpm-store 到 .gitignore

src-tauri/Cargo.toml

@@ -23,6 +23,8 @@ tauri-build = { version = "2", features = [] }
 [dependencies]
 tauri = { version = "2", features = [] }
 tauri-plugin-opener = "2"
+tauri-plugin-process = "2"
+tauri-plugin-updater = "2"
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 rumqttc-v5-next = "0.34"