refactor: 删除nickname字段，统一使用username

- UserInfo实体类删除nickname字段
- UserInfoService.loginOrRegister使用username
- UserController删除nickname相关代码
- 前端所有页面统一使用username
- auth-modal.vue登录时使用username

src/main/java/xuan/controller/UserController.java

@@ -77,7 +77,6 @@ public class UserController {
             data.put("id", user.getId());
             data.put("userId", user.getUserId());
             data.put("openId", user.getOpenId());
-            data.put("nickname", user.getNickname());
             data.put("avatarUrl", user.getAvatarUrl());
             data.put("username", user.getUsername());
             data.put("phone", user.getPhone());
@@ -139,7 +138,6 @@ public class UserController {
                 data.put("id", user.getId());
                 data.put("userId", user.getUserId());
                 data.put("openId", user.getOpenId());
-                data.put("nickname", user.getNickname());
                 data.put("avatarUrl", user.getAvatarUrl());
                 data.put("username", user.getUsername());
                 data.put("phone", user.getPhone());

src/main/java/xuan/entity/UserInfo.java

@@ -14,9 +14,6 @@ public class UserInfo {
     @Column(nullable = false, unique = true, length = 64)
     private String openId;
     
-    @Column(length = 50)
-    private String nickname;
-    
     @Column(length = 255)
     private String avatarUrl;
     
@@ -63,9 +60,6 @@ public class UserInfo {
     public String getOpenId() { return openId; }
     public void setOpenId(String openId) { this.openId = openId; }
     
-    public String getNickname() { return nickname; }
-    public void setNickname(String nickname) { this.nickname = nickname; }
-    
     public String getAvatarUrl() { return avatarUrl; }
     public void setAvatarUrl(String avatarUrl) { this.avatarUrl = avatarUrl; }
     

src/main/java/xuan/service/UserInfoService.java

@@ -22,19 +22,18 @@ public class UserInfoService {
     @Autowired
     private CoinConsumeRecordRepository coinConsumeRecordRepository;
     
-    public UserInfo loginOrRegister(String openId, String nickname, String avatarUrl) {
+    public UserInfo loginOrRegister(String openId, String username, String avatarUrl) {
         UserInfo user = userInfoRepository.findByOpenId(openId);
         if (user != null) {
-            user.setNickname(nickname);
+            user.setUsername(username);
             user.setAvatarUrl(avatarUrl);
             return userInfoRepository.save(user);
         }
         
         user = new UserInfo();
         user.setOpenId(openId);
-        user.setNickname(nickname);
+        user.setUsername(username);
         user.setAvatarUrl(avatarUrl);
-        user.setUsername(generateUsername());
         user.setUserId(generateUserId());
         user.setVipLevel(0);
         user.setStreakDays(0);