Code cleanup: Add constants to header for dark mode, buffer sizes and Unicode support. Windows and OS/2 can both be built without Unicode support for legacy platforms and apps. Some new Windows features require Unicode (notifications, edge) and Unicode is buggy on OS/2. Can now check if Unicode is supported with the DW_FEATURE_UTF8_UNICODE feature test. Dark mode constants added DW_DARK_MODE_DISABLED/BASIC/FULL/FORCED. Win: Include dw.h in the WinToast glue for the constants, and improve safety in Edge glue.

[Desktop Entry]
Name=Dynamic Windows Test
Exec=@prefix@/bin/dwtest 
Terminal=false
MultipleArgs=false
Type=Application
Categories=Application;Development;X-Red-Hat-Base;