feat: 完善后端架构和service层实现

- 创建完整的entity实体类体系，包括所有业务实体
- 实现BaseEntity基类，统一管理公共字段
- 创建雪花算法ID生成器和自动填充处理器
- 简化所有mapper接口，只继承BaseMapper
- 重构service层，使用LambdaQueryWrapper进行数据库操作
- 创建BasePageRequest分页查询基类
- 完善用户上下文管理和JWT认证
- 新增WebSocket聊天功能和相关控制器
- 更新前端配置和组件，完善用户认证流程
- 同步数据库建表脚本

backend-distributed/mysql_emotion_museum_final.sql

@@ -633,8 +633,6 @@ CREATE INDEX idx_coze_api_call_start_time ON coze_api_call (start_time);
 
 CREATE INDEX idx_coze_api_call_request_type ON coze_api_call (request_type);
 
-CREATE INDEX idx_coze_api_call_final_status ON coze_api_call (final_status);
-
 CREATE INDEX idx_coze_api_call_client_ip ON coze_api_call (client_ip);
 
 CREATE INDEX idx_coze_api_call_session_id ON coze_api_call (session_id);
@@ -853,10 +851,4 @@ ORDER BY
     TABLE_NAME;
 
 -- 提交事务
-COMMIT;
-
--- 完成消息
-SELECT
-    'Emotion Museum Database v3.0 Final (雪花算法主键版本) - 开发版本 deployment completed successfully!' as message,
-    NOW () as completion_time,
-    'All tables dropped and recreated with VARCHAR(36) primary keys. Development version - data will be lost on re-execution!' as description;
+COMMIT;