feat(system): 实现注册码功能并优化用户注册流程

- 新增注册码生成和验证功能- 实现系统设置管理，包括注册功能开关
- 更新前端界面，增加系统管理和注册码相关功能
- 修改数据库结构，添加系统设置和注册码表

biji-houdaun/src/main/java/com/test/bijihoudaun/controller/UserController.java

@@ -2,6 +2,8 @@ package com.test.bijihoudaun.controller;
 
 import com.test.bijihoudaun.common.response.R;
 import com.test.bijihoudaun.entity.User;
+import com.test.bijihoudaun.service.RegistrationCodeService;
+import com.test.bijihoudaun.service.SystemSettingService;
 import com.test.bijihoudaun.service.UserService;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.Parameter;
@@ -24,14 +26,27 @@ public class UserController {
     @Autowired
     private UserService userService;
 
+    @Autowired
+    private SystemSettingService systemSettingService;
+
+    @Autowired
+    private RegistrationCodeService registrationCodeService;
+
     @Operation(summary = "用户注册")
     @Parameters({
             @Parameter(name = "username", description = "用户名",required = true),
             @Parameter(name = "password", description = "密码",required = true),
-            @Parameter(name = "email", description = "邮箱",required = true)
+            @Parameter(name = "email", description = "邮箱",required = true),
+            @Parameter(name = "registrationCode", description = "注册码", required = true)
     })
     @PostMapping("/register")
-    public R<User> register(String username, String password, String email){
+    public R<User> register(String username, String password, String email, String registrationCode){
+        if (!systemSettingService.isRegistrationEnabled()) {
+            return R.fail("注册功能已关闭");
+        }
+        if (!registrationCodeService.validateCode(registrationCode)) {
+            return R.fail("无效或已过期的注册码");
+        }
         return R.success(userService.register(username,password,email));
     }