- Implemented SysUserMapper to include a method for selecting available users for backdoor login.
- Created XML mappings for the new backdoor user selection query.
- Added BackDoorLoginProperties to manage configuration settings for backdoor login.
- Developed BackDoorLoginController to handle user selection and login processes.
- Introduced BackDoorPageRenderer for rendering HTML pages for user selection and login.
- Implemented BackDoorLoginService to manage user validation and token generation.
- Added HTML templates for user selection, login, and error handling.
- Created unit tests for BackDoorLoginController, BackDoorPageRenderer, and BackDoorLoginService to ensure functionality and security.
- Documented usage and configuration in test-backdoor-login.md.
