OnUpdate ran in frame-creation order, from a list built before the walk, so a frame hidden by an earlier handler still updated, and strata and level played no part.
The reference's update walk `0x765650` goes through the nine strata from the bottom, each stratum's levels from 0, and each level's list oldest link first. It saves the next frame before each call, so a hide skips a frame before its turn. A frame linked into the level being walked waits a tick; one linked into a level still ahead runs there.
The walk now follows that order, using the link stamps shows and level changes already keep. It checks each frame at its turn and places frames linked or given an `OnUpdate` mid-walk. An EditBox still flushes right after its own `OnUpdate`.
Tests cover the order, mid-walk hides and shows, and a box's flush.
Fixes#742
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
