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/services/tv_service.py

@@ -10,7 +10,7 @@ from app.core.ids import aurora_id, parse_aurora_id
 from app.models.credit import Credit
 from app.models.enums import ArtworkType, CompanyType, SeriesStatus
 from app.models.tv import Series
-from app.repositories import polymorphic, tv_repository
+from app.repositories import polymorphic, trending_repository, tv_repository
 from app.schemas.common import CastCreditOut, CompanyBriefOut, CrewCreditOut, GenreOut, KeywordOut
 from app.schemas.tv import (
     EpisodeBriefOut,
@@ -316,6 +316,30 @@ async def build_series_summaries(
     return out
 
 
+_TRENDING_WINDOWS = ("day", "week")
+
+
+async def list_trending(
+    session: AsyncSession, *, time_window: str, page: int, page_size: int
+) -> SeriesListOut:
+    if time_window not in _TRENDING_WINDOWS:
+        raise InvalidSeriesFilterError(f"unknown time_window: {time_window!r}")
+
+    all_ids = await trending_repository.get_trending_entity_ids(
+        session, entity_type="series", time_window=time_window
+    )
+    total = len(all_ids)
+    start = (page - 1) * page_size
+    page_ids = all_ids[start : start + page_size]
+    series_rows = await tv_repository.get_series_by_ids(session, page_ids)
+    results = [await _series_summary_from_row(session, s) for s in series_rows]
+    total_pages = (total + page_size - 1) // page_size if total else 0
+
+    return SeriesListOut(
+        page=page, page_size=page_size, total_results=total, total_pages=total_pages, results=results
+    )
+
+
 async def list_series(
     session: AsyncSession,
     *,