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+聊天服务器API文档
+1. 服务器概述
+‌服务类型‌: 混合服务(HTTP + Socket)
+‌HTTP端口‌: 5001 (Flask)
+‌Socket端口‌: 8888
+‌数据库‌: SQLite (usr.db)
+2. HTTP API接口
+2.1 用户注册
+‌端点‌: POST /api/register
+‌请求格式‌:
+json
+Copy Code
+{
+    "username": "string",
+    "password": "string"
+}
+‌成功响应‌:
+json
+Copy Code
+{
+    "success": true,
+    "message": "User registered successfully"
+}
+‌错误响应‌:
+403: 用户名已存在
+500: 服务器内部错误
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