* fix(macos): defer isOverflowing mutation to break SwiftUI render loop
measuredHeight() mutated model.isOverflowing synchronously during a SwiftUI
view update cycle. The onChange(of: attributed) handler triggered
updateWindowFrame → targetFrame → measuredHeight, which set isOverflowing,
invalidating the view and re-triggering onChange — an infinite render loop
causing 100% CPU pinwheel.
Fix: defer the isOverflowing mutation via DispatchQueue.main.async with an
equality guard to prevent redundant updates. The frame calculation itself
remains synchronous so the window size is correct immediately.
Fixes#43480
* fix(macos): preserve latest overflow measurement
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Co-authored-by: Vincent Koc <25068+vincentkoc@users.noreply.github.com>
