Channel, Subscription, Video, SearchFind, ExploredChannel and BlockedChannel (and LIVE_OR_UPCOMING)
leave app/models.py for app/catalog/models.py; app.tables registers them. The User↔Subscription
relationship names its other side as a type only. No schema change.
A failed connection or token step answered nothing about the channel, yet stamped it: one proxy blip
during an RSS blackout delayed every due channel by a whole window. YouTubeError now names the
endpoint that answered; a failure no endpoint gave, or a spent quota, ends the round and stamps
nothing.
A channel whose uploads playlist also failed was never stamped, so a terminated channel was charged
again on every 20-minute poll instead of once per rss_fallback_hours. An upstream quotaExceeded now
stops the round instead of charging every remaining channel the same refusal.
YouTube's RSS goes dark per channel for hours (prod 2026-09-18/19: 393 of
396 feeds answered 404 for four hours, sticky per channel, so a retry does
not help), and nothing else read a followed channel's new uploads. A
channel whose feed has not answered for `rss_fallback_hours` (admin knob,
default 2, 0 = off) now gets one page of its uploads playlist through the
Data API (1 unit), at most once per window, yielding to the backfill
reserve. Spend is attributed to its own quota action.
peter