Fixed multiple compiler warnings across the codebase including:
1. Removed unused variable 'byte_count' in DBackingStoreProxy
2. Added [[maybe_unused]] attribute to unused functions
getInputRectangleY and atomName
3. Removed Q_DECL_HIDDEN from several class declarations
4. Fixed initialization order in DXcbXSettingsPrivate constructor
5. Removed negative check for function pointer offset in VtableHook
6. Added override keyword to test class methods
7. Added Q_UNUSED for unused parameters in various functions
8. Fixed potential integer comparison issues in DWaylandInterfaceHook
9. Added proper type casting for window property comparison
10. Fixed Qt version conditional compilation in
DPlatformBackingStoreHelper

These changes improve code quality by:
- Removing dead code
- Making unused function intentions explicit
- Following modern C++ practices
- Ensuring proper initialization order
- Preventing potential integer comparison issues
- Maintaining cross-version Qt compatibility

Influence:
1. Verify wallpaper sharing functionality still works
2. Test input handling in text fields
3. Validate platform settings behavior
4. Check XSettings integration
5. Test vtable hooking functionality
6. Verify unit tests still pass
7. Test wayland window splitting functionality
8. Validate high DPI scaling behavior

fix: 修复各种编译器警告

修复了代码库中的多个编译器警告，包括：
1. 移除DBackingStoreProxy中未使用的变量'byte_count'
2. 为未使用的函数getInputRectangleY和atomName添加[[maybe_unused]]属性
3. 从多个类声明中移除Q_DECL_HIDDEN
4. 修复DXcbXSettingsPrivate构造函数中的初始化顺序
5. 移除VtableHook中对函数指针偏移量的负值检查
6. 为测试类方法添加override关键字
7. 为多个未使用的参数添加Q_UNUSED
8. 修复DWaylandInterfaceHook中潜在的整数比较问题
9. 为窗口属性比较添加适当的类型转换
10. 修复DPlatformBackingStoreHelper中的Qt版本条件编译

这些改进通过以下方式提升代码质量：
- 移除无用代码
- 明确未使用函数的意图
- 遵循现代C++实践
- 确保正确的初始化顺序
- 防止潜在的整数比较问题
- 保持跨Qt版本的兼容性

Influence:
1. 验证壁纸共享功能是否仍然正常工作
2. 测试文本字段中的输入处理
3. 验证平台设置行为
4. 检查XSettings集成
5. 测试vtable钩子功能
6. 验证单元测试是否仍然通过
7. 测试wayland窗口分割功能
8. 验证高DPI缩放行为