refactor(invite): 移除用户主动生成邀请码功能

- 删除 InviteCodeRespVO.java VO 类
- 移除 KeyboardUserInviteCodesService 及其实现中的 createInviteCode/getUserInviteCode 方法
- 删除 UserController 中 /inviteCode 查询接口
- 注册流程不再自动为用户创建邀请码，仅保留绑定逻辑

src/main/java/com/yolo/keyborad/controller/UserController.java

@@ -8,12 +8,9 @@ import com.yolo.keyborad.model.dto.AppleLoginReq;
 import com.yolo.keyborad.model.dto.user.*;
 import com.yolo.keyborad.model.entity.KeyboardFeedback;
 import com.yolo.keyborad.model.entity.KeyboardUser;
-import com.yolo.keyborad.model.entity.KeyboardUserInviteCodes;
-import com.yolo.keyborad.model.vo.user.InviteCodeRespVO;
 import com.yolo.keyborad.model.vo.user.KeyboardUserInfoRespVO;
 import com.yolo.keyborad.model.vo.user.KeyboardUserRespVO;
 import com.yolo.keyborad.service.IAppleService;
-import com.yolo.keyborad.service.KeyboardUserInviteCodesService;
 import com.yolo.keyborad.service.UserService;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.Parameter;
@@ -46,9 +43,6 @@ public class UserController {
     @Resource
     private com.yolo.keyborad.service.KeyboardFeedbackService feedbackService;
 
-    @Resource
-    private KeyboardUserInviteCodesService inviteCodesService;
-
     /**
      * 苹果登录
      *
@@ -133,15 +127,6 @@ public class UserController {
         return ResultUtils.success(feedbackService.save(feedback));
     }
 
-    @GetMapping("/inviteCode")
-    @Operation(summary = "查询邀请码", description = "查询用户自己的邀请码")
-    public BaseResponse<InviteCodeRespVO> getInviteCode() {
-        long userId = StpUtil.getLoginIdAsLong();
-        KeyboardUserInviteCodes inviteCode = inviteCodesService.getUserInviteCode(userId);
-        InviteCodeRespVO respVO = BeanUtil.copyProperties(inviteCode, InviteCodeRespVO.class);
-        return ResultUtils.success(respVO);
-    }
-
     @PostMapping("/bindInviteCode")
     @Operation(summary = "绑定邀请码", description = "用户填写邀请码进行绑定")
     public BaseResponse<Boolean> bindInviteCode(@RequestBody BindInviteCodeDTO bindInviteCodeDTO) {