The PiP close-button detection sampled the Flutter lifecycle once,
300ms after the PiP flag flipped off. On expand-back, `resumed` often
arrives later than that (the exit animation has to finish and the
window regain focus first), so returning to the app was misclassified
as an X-button dismissal and playback was paused. Wait up to 2s for
`resumed` (bailing out early on dispose or PiP re-entry) and only
pause when it never arrives. Prep 1.5.2.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012u551tgpy3zxxjtvjBx77x