Records both fixed defects with their xterm mechanisms, the reveal/wake call
graph, why every e2e oracle for a stale canvas was proven blind, how to arm the
in-app render-desync sentinel on real hardware, and the one unverified lead
(dimension staleness) that would explain why a window resize specifically is
the repair users find. Refs STA-2694.
Co-authored-by: Orca <help@stably.ai>