feat(user): set default avatar URL for new users and update existing user avatar retrieval

Author: LiggMax

flow-client/src/main/java/com/ligg/flowclient/service/impl/UserOauthServiceImpl.java

@@ -230,7 +230,7 @@ private static String resolveAvatar(BangumiUserinfoVO me) {
                 return Utils.imgUrlToWsrvCdn(me.avatar().large());
             }
         }
-        return null;
+        return Constants.DEFAULT_USER_AVATAR_URL;
     }
 
     private static BangumiBindVo toBindVo(BangumiUserinfoVO me) {

flow-client/src/main/java/com/ligg/flowclient/service/impl/UserServiceImpl.java

@@ -75,7 +75,7 @@ public void register(RegisterDto registerDto) {
         newUser.setPassword(PasswordUtils.hash(registerDto.getPassword()));
         newUser.setNickname(registerDto.getEmail().split("@")[0]);
         newUser.setCreateTime(Instant.now().getEpochSecond());
-
+        newUser.setAvatar(Constants.DEFAULT_USER_AVATAR_URL);
         try {
             userMapper.insert(newUser);
         } catch (DuplicateKeyException e) {