WHY: the /podcasts search box filtered feed CARDS only (title, display
name, host, publisher, feed description). D14's episode search existed
only as the /api/podcasts/search endpoint and was never wired into the
page — searching 'Quarter' (present only in episode titles) cleared the
grid while 'Trader' (feed metadata) survived.
The page query now consults SearchMyPodcastEpisodes (subscription-scoped
via RLS — the caller's identity) when a query is present; a feed
surfaces when its OWN metadata OR any of its episodes matches, with an
'N matching episode(s)' badge on the card.
PIN: SSR test with a needle that exists only in an episode title — the
feed must surface with the match count.