桌面 GUI 外链修复 + 主题顺序调整（含结构扁平化进行中的工作区基线）

- 集成 tauri-plugin-opener：Cargo/lib.rs/capabilities/npm 四处接线，新增 src/openExternal.ts（桌面走 opener，浏览器回退 window.open，相对路径绝对化）
- 关于页 4 个链接、活动栏官网菜单、代理错误横幅 2 处健康检查链接全部改走 openExternal，桌面端可正常跳转
- 设置→外观 主题顺序调整为 深色/浅色/跟随系统
- release 二进制重编并验证（浏览器实测关于页链接可开文档页）
- 附带工作区中未提交的扁平化重构现状（另一会话进行中）
- homepage 落地页与文档终检通过（8787 / 与 /docs 双 200）

src-tauri/tauri.conf.json

@@ -0,0 +1,45 @@
+{
+  "$schema": "https://schema.tauri.app/config/2",
+  "productName": "OpsxAPI",
+  "version": "0.1.0",
+  "identifier": "com.opsx.api",
+  "build": {
+    "beforeDevCommand": "bash -lc 'curl -fsS http://127.0.0.1:5173 >/dev/null 2>&1 || npm run dev'",
+    "devUrl": "http://127.0.0.1:5173",
+    "beforeBuildCommand": "npm run build",
+    "frontendDist": "../dist"
+  },
+  "app": {
+    "windows": [
+      {
+        "title": "OpsxAPI",
+        "titleBarStyle": "Visible",
+        "hiddenTitle": true,
+        "width": 1280,
+        "height": 800,
+        "minWidth": 1040,
+        "minHeight": 680,
+        "resizable": true,
+        "fullscreen": false,
+        "label": "main"
+      }
+    ],
+    "security": {
+      "csp": null
+    }
+  },
+  "bundle": {
+    "active": true,
+    "targets": "all",
+    "icon": [
+      "icons/32x32.png",
+      "icons/128x128.png",
+      "icons/128x128@2x.png",
+      "icons/icon.icns",
+      "icons/icon.ico"
+    ],
+    "category": "DeveloperTool",
+    "shortDescription": "OpsxAPI — API workbench",
+    "longDescription": "OpsxAPI is an API workbench for ops and developers: HTTP / WebSocket, one React UI, Web and Desktop share Transport."
+  }
+}