chore: 版本号 0.1.0 → 0.9.0-beta.1 + updater 插件预留

- package.json / tauri.conf.json: version 更新为 0.9.0-beta.1
- tauri.conf.json: 添加 plugins.updater 空壳配置 + createUpdaterArtifacts
- Cargo.toml: 添加 tauri-plugin-updater 依赖
- lib.rs: 注册 updater 插件 (空壳，部署时配置 HTTPS 端点 + Ed25519 密钥)

desktop/src-tauri/tauri.conf.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://schema.tauri.app/config/2",
   "productName": "ZCLAW",
-  "version": "0.1.0",
+  "version": "0.9.0-beta.1",
   "identifier": "com.zclaw.desktop",
   "build": {
     "beforeDevCommand": "pnpm dev",
@@ -33,6 +33,13 @@
       "icons/128x128@2x.png",
       "icons/icon.icns",
       "icons/icon.ico"
-    ]
+    ],
+    "createUpdaterArtifacts": "v2Compatible"
+  },
+  "plugins": {
+    "updater": {
+      "endpoints": [],
+      "pubkey": ""
+    }
   }
 }