Replaces the user-visible "Audio paused — tap anywhere to resume"
notice (which I added in 305c60f without remembering fox already
tried and rejected it in 6c9d1b8 → 24bfc81: "tap-anywhere added
user-visible noise").
Real mechanism fox identified: hard refresh on the HOST fixed the
phone — because the republish triggers a fresh ontrack on the phone,
which leases a NEW pool element from the pre-blessed pool with
intact autoplay engagement. Mirror that automatically without user
interaction: when the 5s telemetry tick sees a remoteAudio element
wedged (rs>=2 paused at ct=0 with a live srcObject), tear it out,
lease a fresh pool element, rebind the same MediaStream, play().
Silent recovery — no notice, no tap, no user-visible noise.
Doesn't replace the original pool blessing (still primed at entry
click), just provides a continuous self-heal whenever the
srcObject-swap kills engagement on an existing element.