- Added AddCategoryReqVO for category creation with validation
- Created AdminCategoryController with endpoints for add, list, delete and select operations
- Implemented AdminCategoryService interface and its methods
- Added Category entity with JPA annotations and logical delete support
- Created CategoryRepository extending JpaRepository with custom query methods
- Added SQL table creation script for t_category with indexes and constraints
- Implemented PageResponse utility for handling paginated results
- Added FindCategoryPageListReqVO and FindCategoryPageListRspVO for pagination
- Included DeleteCategoryReqVO for category deletion requests
- Updated Jackson configuration to ignore unknown properties
- Added base page query model and user info response VO
- Fixed typo in response code enum for user not exist error
