feat: 内置虾盘云 + 设备指纹绑定 + Release 流水线

- 新增 portable/lib/{fingerprint,xiapan-client,bootstrap-xiapan}.mjs：
  跨平台设备指纹（Win USB/disk + Mac UUID + Linux machine-id + seed 兜底）
  生成 sk-uc-{fingerprint} 形式的虾盘云 apiKey，启动时 merge 到 openclaw.json
- Config.html 顶部新增「已绑定虾盘云」横幅：指纹来源 + Key + 余额 + 充值/解绑
- config-server 增加 /api/xiapan/{status,bind,unbind} 三个端点
- Electron app 在 whenReady 调 bootstrap，新增 sync-lib.js 让 build 前自动同步
- 锁 OpenClaw 版本到 2026.4.29（OPENCLAW_VERSION 单一来源）
- 删除死代码 portable/充值.html
- 新增 .github/workflows/release.yml：tag 触发，出 portable zip + Electron exe/dmg
- README 增加内置虾盘云说明 + 直接下载发行版指引

u-claw-app/package.json

@@ -7,13 +7,14 @@
   "license": "MIT",
   "homepage": "https://u-claw.org",
   "scripts": {
-    "start": "electron .",
-    "dev": "electron . --dev",
-    "build:mac": "electron-builder --mac",
-    "build:mac-arm64": "electron-builder --mac --arm64",
-    "build:mac-x64": "electron-builder --mac --x64",
-    "build:win": "electron-builder --win",
-    "build:all": "electron-builder --mac --win",
+    "sync-lib": "node scripts/sync-lib.js",
+    "start": "npm run sync-lib && electron .",
+    "dev": "npm run sync-lib && electron . --dev",
+    "build:mac": "npm run sync-lib && electron-builder --mac",
+    "build:mac-arm64": "npm run sync-lib && electron-builder --mac --arm64",
+    "build:mac-x64": "npm run sync-lib && electron-builder --mac --x64",
+    "build:win": "npm run sync-lib && electron-builder --win",
+    "build:all": "npm run sync-lib && electron-builder --mac --win",
     "postinstall": "electron-builder install-app-deps"
   },
   "build": {