Avoid redraws for event-loop wake notifications

[elcritch]

Problem

Merenda treated every event-loop activity result as a reason to redraw every visible window. Siwin uses the same activity result for native input and event-loop wake notifications, so periodic worker traffic caused unchanged frames to be presented repeatedly.

Change

• remove the blanket repaint after pollEvents and waitEvents
• keep view and layout invalidation as the application redraw trigger
• pin Siwin to the native-damage fix in levovix0/siwin#55
• add focused coverage for wake-only work, targeted invalidation, clean onRender, and native damage behavior
• document the render scheduling contract

Siwin now schedules onRender for X11 Expose and damaged WinAPI WM_PAINT events, while wake notifications and unrelated native events leave clean windows untouched.

Validation

• atlas-run tests tests/integrations/nativewindowrepaint.nim -- --hints:off --warnings:off
• nim check --os:linux --hints:off --warnings:off --errorMax:3 tests/integrations/nativewindowrepaint.nim
• nim check --os:windows -d:figdraw.opengl --hints:off --warnings:off --errorMax:3 tests/integrations/nativewindowrepaint.nim
• Siwin focused event-loop test passed on macOS; Linux and Windows compile checks passed.

The full suites are being run separately as requested.

[elcritch]

@Buegel26 could you checkout this PR and make sure the rendering remains good? This works on the previous fixes but also fixes event efficiency.

[Buegel26]

Local repo: commit 199c4bb (HEAD -> main, origin/main, origin/HEAD)

No issues encountered - works for me, no visible changes in behaviour or new weird things. Rendering is smooth for me.

@elcritch Any further things I should consider when testing this?

[Buegel26]

BTW: sorry for the delays in reacting sometimes... you are incredibly fast. And inform me when I starting to annoy you with issues :-)

[elcritch]

Local repo: commit 199c4bb (HEAD -> main, origin/main, origin/HEAD)

No issues encountered - works for me, no visible changes in behaviour or new weird things. Rendering is smooth for me.

Excellent! That means the siwin fix works which simplifies event handling and drawing refreshes.

@elcritch Any further things I should consider when testing this?

Nope just that. Making sure previous rendering glitches didn’t come back.

[elcritch]

BTW: sorry for the delays in reacting sometimes... you are incredibly fast. And inform me when I starting to annoy you with issues :-)

No worries about that! I appreciate the issues.

lol yeah been a bit hyper focused lately on it lately.. Want to get it so I can use it for work.

Thanks for testing, it really helps.