Bug 1: Ardour flushes stems in ~12MB bursts every ~3s — a 2s stop-grace read
every gap as stop/start and reset the clock eleven times in one 20s take.
Grace is now 6s, with the measured cadence in the comment.
Bug 2: transport-button feedback IS bit-gated — /set_surface feedback 8→9
(button-status + heartbeat); the 'not bit-gated' reading died on the live rig.
Bug 3: a mute lens is not a dissenting lens — combine_rec only counts OSC when
arm AND roll are concrete, so 'connected but silent' can no longer stamp
conflict:true on ground truth. src labeling now names actual contributors.
Regression tests drive RecPass through the real flush cadence; 169 green.
