Add watch providers (where to stream/rent/buy)

New TMDb integration end to end: append_to_response "watch/providers",
normalizer parsing grouped by country/monetization type, a WatchProvider
catalog entry (external-id keyed, same get_or_create pattern as Company/
Collection/Person) + polymorphic WatchProviderOffering table (new
migration 0002), ingestion write (including provider logos via the
existing Artwork table), and API exposure -- embedded on movie/series
detail plus a dedicated /watch-providers sub-route, shaped to mirror
TMDb's own response for easy porting.

Note: this data comes from JustWatch via TMDb and carries its own
attribution requirement separate from TMDb's general one -- flagged in
docs/api.md, must be satisfied before showing this in the frontend.

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

app/services/common.py

@@ -2,6 +2,8 @@
 
 from __future__ import annotations
 
+from sqlalchemy.ext.asyncio import AsyncSession
+
 from app.core.ids import aurora_id
 from app.models.artwork import Artwork
 from app.models.credit import Credit
@@ -9,6 +11,8 @@ from app.models.enums import ArtworkType
 from app.models.movie import MovieAlternateTitle, ReleaseDate
 from app.models.tv import SeriesAlternateTitle
 from app.models.video import Video
+from app.models.watch_provider import WatchProviderOffering
+from app.repositories import polymorphic
 from app.schemas.common import (
     AlternateTitleOut,
     ArtworkOut,
@@ -19,6 +23,8 @@ from app.schemas.common import (
     PersonBriefOut,
     ReleaseDateOut,
     VideoOut,
+    WatchProviderOut,
+    WatchProviderRegionOut,
 )
 
 
@@ -110,6 +116,34 @@ def pick_certification(release_dates: list[ReleaseDate], *, preferred_country: s
     return fallback
 
 
+async def build_watch_providers_out(
+    session: AsyncSession, offerings: list[WatchProviderOffering]
+) -> dict[str, WatchProviderRegionOut]:
+    out: dict[str, WatchProviderRegionOut] = {}
+    logo_cache: dict[object, str | None] = {}
+    for row in offerings:
+        region = out.get(row.country_code)
+        if region is None:
+            region = WatchProviderRegionOut(link=row.link)
+            out[row.country_code] = region
+        elif region.link is None and row.link is not None:
+            region.link = row.link
+
+        wp = row.watch_provider
+        if wp.id not in logo_cache:
+            logos = await polymorphic.get_artwork(session, "watch_provider", wp.id, ArtworkType.LOGO)
+            logo_cache[wp.id] = primary_artwork_path(logos, ArtworkType.LOGO)
+
+        entry = WatchProviderOut(
+            id=aurora_id("watch_provider", str(wp.id)),
+            name=wp.name,
+            logo_path=logo_cache[wp.id],
+            display_priority=row.display_priority,
+        )
+        getattr(region, row.monetization_type).append(entry)
+    return out
+
+
 def split_credits(
     credits_: list[Credit], profile_paths: dict | None = None
 ) -> tuple[list[CastCreditOut], list[CrewCreditOut]]: