Update pom.xml for MyBatis Plus integration and downgrade Spring Boot version; refactor validation imports from Jakarta to Javax; modify mappers to extend BaseMapper for CRUD operations; clean up unused MyBatis-Flex mappers; adjust application.yml for MyBatis Plus configuration.

src/main/java/com/gameplatform/server/service/UserService.java

@@ -28,7 +28,7 @@ public class UserService {
      * 根据ID获取用户账户
      */
     public Mono<AccountResponse> getById(Long id) {
-        return Mono.fromCallable(() -> userAccountMapper.findById(id))
+        return Mono.fromCallable(() -> userAccountMapper.selectById(id))
                 .subscribeOn(Schedulers.boundedElastic())
                 .filter(Objects::nonNull)
                 .map(this::toAccountResponse);

src/main/java/com/gameplatform/server/service/account/AccountService.java

@@ -68,7 +68,7 @@ public class AccountService {
     }
 
     public Mono<AccountResponse> get(Long id) {
-        return Mono.fromCallable(() -> mapper.findById(id))
+        return Mono.fromCallable(() -> mapper.selectById(id))
                 .subscribeOn(Schedulers.boundedElastic())
                 .map(this::toResp);
     }
@@ -76,7 +76,7 @@ public class AccountService {
     @Transactional
     public Mono<AccountResponse> update(Long id, AccountUpdateRequest req) {
         return Mono.fromCallable(() -> {
-                    UserAccount db = mapper.findById(id);
+                    UserAccount db = mapper.selectById(id);
                     if (db == null) return null;
                     
                     // 验证用户名唯一性（如果要更新用户名）
@@ -120,8 +120,8 @@ public class AccountService {
                         }
                     }
                     
-                    mapper.update(patch);
-                    return mapper.findById(id);
+                    mapper.updateById(patch);
+                    return mapper.selectById(id);
                 })
                 .subscribeOn(Schedulers.boundedElastic())
                 .map(this::toResp);

src/main/java/com/gameplatform/server/service/link/LinkGenerationService.java

@@ -59,7 +59,7 @@ public class LinkGenerationService {
         }
 
         // 获取操作者账户信息
-        UserAccount operator = userAccountMapper.findById(operatorId);
+        UserAccount operator = userAccountMapper.selectById(operatorId);
         if (operator == null) {
             throw new IllegalArgumentException("操作者账户不存在");
         }
@@ -127,7 +127,7 @@ public class LinkGenerationService {
             UserAccount patch = new UserAccount();
             patch.setId(operator.getId());
             patch.setPointsBalance(after);
-            userAccountMapper.update(patch);
+            userAccountMapper.updateById(patch);
         }
 
         GenerateResult result = new GenerateResult();