Fix job_id mismatch between ingestion enqueue and status endpoints

POST /api/v1/admin/ingest/movie returned arq's own internal queue
job id, but GET /api/v1/admin/ingest/jobs/{job_id} looked up our
IngestionJob DB row by its own UUID -- a completely different id that
didn't even exist yet at enqueue time (the row was only created once
the worker picked up the task). Every status poll 404'd.

Fix: create the IngestionJob row synchronously in the enqueue endpoint
(reusing the existing idempotency-key logic, so repeat enqueues for
the same tmdb_id reuse the same row rather than creating duplicates),
pass its real id into the arq task, and have the worker update that
row instead of creating a new one.

Found by actually running the milestone end-to-end: enqueue a real
TMDb ingestion, then poll its status.

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

app/services/ingestion/runner.py

@@ -38,7 +38,18 @@ async def _require_job(session: AsyncSession, job_id: uuid.UUID) -> IngestionJob
     return job
 
 
-async def _create_job(job_type: str, entity_type: str, external_id: str) -> uuid.UUID:
+async def get_or_create_ingestion_job(job_type: str, entity_type: str, external_id: str) -> uuid.UUID:
+    """Create the DB-tracked `IngestionJob` row (or return the existing one
+    for this provider+entity+external_id, keyed by `idempotency_key`)
+    without running the pipeline.
+
+    Called synchronously from the admin endpoint, *before* enqueuing to arq,
+    specifically so the HTTP response can return a `job_id` that
+    `GET /admin/ingest/jobs/{job_id}` can immediately resolve — arq's own
+    queue-internal job id is a different, unrelated identifier and was
+    never valid here.
+    """
+
     idempotency_key = f"tmdb:{entity_type}:{external_id}"
     async with session_scope() as session:
         provider_row = await get_or_create_provider(session, "tmdb", "The Movie Database (TMDb)")
@@ -53,8 +64,9 @@ async def _create_job(job_type: str, entity_type: str, external_id: str) -> uuid
         return job.id
 
 
-async def run_movie_ingestion(external_id: str) -> uuid.UUID:
-    job_id = await _create_job("movie_sync", "movie", external_id)
+async def run_movie_ingestion(job_id: uuid.UUID, external_id: str) -> uuid.UUID:
+    """Run the pipeline for an `IngestionJob` row that already exists (see
+    `get_or_create_ingestion_job`) — this never creates the row itself."""
 
     async with session_scope() as session:
         job = await _require_job(session, job_id)
@@ -78,8 +90,9 @@ async def run_movie_ingestion(external_id: str) -> uuid.UUID:
         await provider.aclose()
 
 
-async def run_person_ingestion(external_id: str) -> uuid.UUID:
-    job_id = await _create_job("person_sync", "person", external_id)
+async def run_person_ingestion(job_id: uuid.UUID, external_id: str) -> uuid.UUID:
+    """Run the pipeline for an `IngestionJob` row that already exists (see
+    `get_or_create_ingestion_job`) — this never creates the row itself."""
 
     async with session_scope() as session:
         job = await _require_job(session, job_id)