The footer froze at '?REC 00:10' on the glass during the first real take. No
code-level freeze reproduced; what WAS wrong: the ghost mirror recomputed state
instead of mirroring device writes (so diagnosis lied), and the 2s tick wrote
unconditionally with no dedup. Now: _home_cache records the string actually
sent, the tick writes only on change (repaint ≤2s, revert ≤2s after stale), and
the 20s label-reassert forces a full repaint so dedup can never mask a device-
side reset. Hardware verdict awaits the next recorded take.