Changes since v0.0.13:
- New widgets: ListView, SpinControl, RichEdit, TreeView
- TabControl: API improvements, WM_NOTIFY handling fix, and hang prevention
- Menu: new Menu API, support for .rc-defined menus, and Dialog WM_COMMAND handling via OnCommand
- Infrastructure: InitCommonControlsEx; auto-load Msftedit/Riched20; cross-thread SendMessage uses SendMessageTimeout to avoid deadlocks
- Examples: refreshed basic demo and added MessageBox/widget demos