Add trending movies/series, refreshed on a schedule

Mirrors TMDb's own /trending/{movie|tv}/{day|week} ranking rather than
Aurora computing trending itself from popularity deltas -- that would
require re-syncing the entire catalog on a schedule, infeasible at any
real scale, whereas TMDb already computes this well from signals (real
view/search velocity) Aurora has no access to.

New: TrendingEntry model + migration 0003, MetadataProvider.get_trending
(concrete/optional, like aclose(), so existing test fakes don't all need
updating), refresh_trending() which actually ingests each trending item
(only ~20 per window, cheap enough to fully ingest rather than apply the
never-fabricate-a-stub rule recommendations uses), a twice-daily arq cron
job (WorkerSettings.cron_jobs, new to this codebase), a manual admin
trigger for right after a deploy, and GET /movies/trending + GET
/series/trending.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

app/workers/worker.py

@@ -10,6 +10,7 @@ each job is picked up by exactly one worker.
 from __future__ import annotations
 
 from arq.connections import RedisSettings
+from arq.cron import cron
 
 from app.core.config import get_settings
 from app.core.logging import configure_logging, get_logger
@@ -20,6 +21,7 @@ from app.workers.tasks import (
     ingest_person_task,
     ingest_season_task,
     ingest_series_task,
+    refresh_trending_task,
 )
 
 logger = get_logger(__name__)
@@ -43,6 +45,10 @@ class WorkerSettings:
         ingest_collection_task,
         download_artwork_task,
     ]
+    # Twice a day (UTC) rather than run_at_startup=True -- a worker
+    # container restart (common during deploys) must not hammer TMDb with
+    # a full trending refresh every time it comes up.
+    cron_jobs = [cron(refresh_trending_task, hour={3, 15}, minute=0)]
     on_startup = startup
     on_shutdown = shutdown
     redis_settings = RedisSettings.from_dsn(get_settings().REDIS_URL)