feat: OpsxAPI v1.0 全协议接口工作台

- 六协议调试：HTTP/GraphQL/WebSocket/SSE/Socket.IO/MQTT
- 集合树/多标签/多环境变量/历史记录，localStorage 持久化
- 导入：OpenAPI 2/3/3.1、Postman、Apifox、Apipost、cURL、HAR、
  Insomnia、Hoppscotch、Markdown（自动识别，21 个单测覆盖）
- 导出：OpenAPI 3.0 JSON/YAML、Postman v2.1、Markdown 文档、
  全量备份；单请求生成 cURL/fetch/Python/Go 代码
- Gin 服务：HTTP 代理、NDJSON 流式代理（SSE 透传）、
  WebSocket 隧道（浏览器自定义握手 Header）
- 内置产品官网 /home 与用户文档站 /docs（SSR，随二进制交付）
- lucide 图标体系 + 品牌标识（Logo/favicon），明暗双主题
- 环境变量：彩色徽标切换器、管理弹窗、{{ 自动补全

api/openapi.yaml

@@ -0,0 +1,69 @@
+openapi: 3.0.3
+info:
+  title: OpsxAPI Server
+  version: 0.1.0
+  description: Minimal health + HTTP proxy API
+servers:
+  - url: http://127.0.0.1:8787
+paths:
+  /health:
+    get:
+      summary: Health check
+      responses:
+        "200":
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  ok: { type: boolean }
+                  service: { type: string }
+  /v1/proxy/http:
+    post:
+      summary: Proxy an HTTP request
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: "#/components/schemas/HttpSpec"
+      responses:
+        "200":
+          description: Proxied result
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/HttpResult"
+components:
+  schemas:
+    HttpSpec:
+      type: object
+      required: [method, url]
+      properties:
+        method:
+          type: string
+          enum: [GET, POST, PUT, PATCH, DELETE]
+        url: { type: string }
+        headers:
+          type: object
+          additionalProperties: { type: string }
+        query:
+          type: object
+          additionalProperties: { type: string }
+        body:
+          type: object
+          properties:
+            mode: { type: string, enum: [none, json, raw, form, urlencoded] }
+            raw: { type: string }
+        timeoutMs: { type: integer }
+    HttpResult:
+      type: object
+      properties:
+        status: { type: integer }
+        headers:
+          type: object
+          additionalProperties: { type: string }
+        body: { type: string }
+        timeMs: { type: number }
+        size: { type: integer }