feat: 更新服务 — ZIP下载/备份/回滚/重启

UpdateService:
- 分支感知: 从 base_config 读取 branch, 拼接 archive/{branch}.zip
- 定时检查: 每6h 拉取 version.json 比对版本
- 更新前自动打包备份 (zip, 保留最新5个)
- 保护用户配置: base_config.yaml / plugins/*/config.yaml / data/
- 子进程 pip install 依赖

API:
- GET /api/updates — 更新状态
- POST /api/updates/check — 手动检查
- POST /api/updates/apply — 执行更新

回滚:
- python main.py --rollback  — 恢复到最新备份
- 无备份时提示

重启:
- .restart_flag 信号文件 → 优雅退出 → systemd 拉起

Co-Authored-By: Claude <noreply@anthropic.com>

config/permissions/pending_requests.json

@@ -482,5 +482,49 @@
       "framework.command.execute"
     ],
     "timestamp": 29386.802027486
+  },
+  "1daf5e1a": {
+    "plugin_name": "example_plugin",
+    "permissions": [
+      "plugin.example.read",
+      "plugin.example.write",
+      "plugin.example.execute",
+      "framework.event.subscribe",
+      "framework.command.execute"
+    ],
+    "timestamp": 29765.65822229
+  },
+  "b2d1dd2e": {
+    "plugin_name": "sentinel",
+    "permissions": [
+      "plugin.sentinel.read",
+      "plugin.sentinel.write",
+      "plugin.network.access",
+      "framework.event.subscribe",
+      "framework.command.execute"
+    ],
+    "timestamp": 29765.666844425
+  },
+  "cbc42132": {
+    "plugin_name": "example_plugin",
+    "permissions": [
+      "plugin.example.read",
+      "plugin.example.write",
+      "plugin.example.execute",
+      "framework.event.subscribe",
+      "framework.command.execute"
+    ],
+    "timestamp": 35916.606768589
+  },
+  "2bd9a945": {
+    "plugin_name": "sentinel",
+    "permissions": [
+      "plugin.sentinel.read",
+      "plugin.sentinel.write",
+      "plugin.network.access",
+      "framework.event.subscribe",
+      "framework.command.execute"
+    ],
+    "timestamp": 35916.627558381
   }
 }