The `titleBarStyle: "Overlay"` setting in tauri.conf.json causes black
screen and crash on Windows due to WebView2 compatibility issues.
Add platform-specific config `tauri.windows.conf.json` to override
titleBarStyle to "Visible" on Windows while keeping the overlay style
on macOS for the immersive UI experience.
Fixes black screen issue on Windows for v3.8.x releases.
