feat: add backdoor login functionality for testing environment

- 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.

ruoyi-admin/src/main/resources/application.yml

@@ -60,6 +60,14 @@ token:
   # 令牌有效期（默认30分钟）
   expireTime: 30
 
+# 测试用户后门登录。默认关闭，只允许在明确的测试 profile 中覆盖开启。
+backdoor:
+  login:
+    enabled: false
+    max-users: 100
+    portal-base-path: /shihezi
+    api-base-path: /api/shihezi
+
 # PageHelper分页插件
 pagehelper:
   helperDialect: oracle