Revert "Use SDL3 windowing by default"

[bdach]

Reverts ppy/osu-framework#6396

Rationale:

• https://github.com/ppy/osu/issues/30641
• https://github.com/ppy/osu/issues/28222
• Apparent general unspecified severe issues with macOS windowing (https://discord.com/channels/188630481301012481/188630652340404224/1306507518134194176)
• https://github.com/ppy/osu/discussions/30647 (wayland issue, so weak reason)

None of this seems hotfixable and users are reporting mass breakage using several communication channels, most of which is a variation of any of the three points above. See

• https://osu.ppy.sh/community/forums/5
• https://osu.ppy.sh/home/changelog/lazer/2024.1115.1

I think this is the best move forward in terms of a hotfix, and we shouldn't attempt SDL3 again until these issues are fixed either by us or upstream (or both...)