Lifts _search_service and its _detect_provider helper. Both bodies are
byte-identical to the originals. The nine enrichment worker handles
(spotify/itunes/mb/lastfm/genius/tidal/qobuz/discogs/audiodb) are
injected via init() right after qobuz is constructed, which is the
last worker to come up — and well before Flask starts accepting
requests, so the route handlers never see unbound workers.
web_server.py: 37245 → 37015 (-230 lines).
