Client wake capture had no health monitoring: after a platform capture
failure (macOS PLAS IPC delegate error -> StopSourceOnError) getUserMedia
stays resolved but the PCM is dead (ended track, halted callbacks, or
endless zeros). The ear kept showing listening while the gateway detector
could never fire, and wake.feed refusals plus feed RPC errors were
swallowed (no onError wired). Add track-ended/stall/silence watchdogs and
consecutive feed-refusal escalation; wire onError to an honest off state
with the reason and lease release. Closes#119089