v1.14.7

fix: auto-recover from live channel cold-start playback artifacts

Fresh channel tunes can produce a frozen frame or heavy dropped-frame
choppiness for the first few seconds, likely from Channels DVR's live
encoder pipeline still ramping up. Diagnostics showed this is front-loaded
(all drops happen early, zero afterward), and manually stopping/restarting
the channel always fixes it. Added a one-shot watchdog that detects the
frozen/choppy pattern in the first several seconds of a live tune and
automatically tears down and recreates the HLS.js instance against the same
manifest URL, mirroring the manual workaround without requiring it.