Add GET /movies and GET /series browse/discover endpoints

The complement to /search for browsing without a query: paginated,
filterable (genre, year, status) and sortable (popularity,
release/air date, rating, title) listings. Offset-based pagination
rather than the Aurora ID cursor scheme, since sorting by
popularity/rating/date doesn't line up with creation-order cursors.

Total count is computed via a window function in the same query as
the page of results, avoiding a second round trip per request. An
invalid filter (malformed genre id, unknown status) is a 422 via a
per-service InvalidMovieFilterError/InvalidSeriesFilterError, caught
before any DB query runs.

build_movie_summary/build_series_summary refactored to share their
row-to-summary logic with the new list path, avoiding a redundant
get_by_id lookup when the row is already in hand.

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

app/services/tv_service.py

@@ -7,7 +7,8 @@ import uuid
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.core.ids import aurora_id, parse_aurora_id
-from app.models.enums import ArtworkType, CompanyType
+from app.models.enums import ArtworkType, CompanyType, SeriesStatus
+from app.models.tv import Series
 from app.repositories import polymorphic, tv_repository
 from app.schemas.common import CompanyBriefOut, GenreOut, KeywordOut
 from app.schemas.tv import (
@@ -16,6 +17,7 @@ from app.schemas.tv import (
     SeasonBriefOut,
     SeasonDetailOut,
     SeriesDetailOut,
+    SeriesListOut,
     SeriesSeasonsOut,
     SeriesSummaryOut,
 )
@@ -34,6 +36,10 @@ class EpisodeNotFoundError(Exception):
     pass
 
 
+class InvalidSeriesFilterError(Exception):
+    pass
+
+
 def _resolve_id(aid: str, expected_type: str, error_cls: type[Exception]) -> uuid.UUID:
     try:
         return uuid.UUID(parse_aurora_id(aid, expected_type=expected_type))
@@ -201,13 +207,8 @@ async def get_episode_detail(session: AsyncSession, episode_aurora_id: str) -> E
     )
 
 
-async def build_series_summary(
-    session: AsyncSession, series_id: uuid.UUID
-) -> SeriesSummaryOut | None:
-    series = await tv_repository.get_series_by_id(session, series_id)
-    if series is None:
-        return None
-    posters = await polymorphic.get_artwork(session, "series", series_id, ArtworkType.POSTER)
+async def _series_summary_from_row(session: AsyncSession, series: Series) -> SeriesSummaryOut:
+    posters = await polymorphic.get_artwork(session, "series", series.id, ArtworkType.POSTER)
     return SeriesSummaryOut(
         id=aurora_id("series", str(series.id)),
         title=series.title,
@@ -220,6 +221,15 @@ async def build_series_summary(
     )
 
 
+async def build_series_summary(
+    session: AsyncSession, series_id: uuid.UUID
+) -> SeriesSummaryOut | None:
+    series = await tv_repository.get_series_by_id(session, series_id)
+    if series is None:
+        return None
+    return await _series_summary_from_row(session, series)
+
+
 async def build_series_summaries(
     session: AsyncSession, series_ids: list[uuid.UUID]
 ) -> list[SeriesSummaryOut]:
@@ -229,3 +239,46 @@ async def build_series_summaries(
         if summary is not None:
             out.append(summary)
     return out
+
+
+async def list_series(
+    session: AsyncSession,
+    *,
+    genre_aurora_id: str | None,
+    year: int | None,
+    status: str | None,
+    sort_by: str,
+    sort_dir: str,
+    page: int,
+    page_size: int,
+) -> SeriesListOut:
+    genre_id: uuid.UUID | None = None
+    if genre_aurora_id is not None:
+        try:
+            genre_id = uuid.UUID(parse_aurora_id(genre_aurora_id, expected_type="genre"))
+        except ValueError as exc:
+            raise InvalidSeriesFilterError(f"invalid genre id: {genre_aurora_id!r}") from exc
+
+    status_enum: SeriesStatus | None = None
+    if status is not None:
+        try:
+            status_enum = SeriesStatus(status)
+        except ValueError as exc:
+            raise InvalidSeriesFilterError(f"unknown series status: {status!r}") from exc
+
+    series_rows, total = await tv_repository.list_series(
+        session,
+        genre_id=genre_id,
+        year=year,
+        status=status_enum,
+        sort_by=sort_by,
+        sort_dir=sort_dir,
+        limit=page_size,
+        offset=(page - 1) * page_size,
+    )
+    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
+    )