Why:
- Ingested chunks need to become searchable Qdrant points before the upload
response returns, with tenant/domain isolation and a safe re-ingestion
story per ADR-0001/0017.
Changes:
- src/application/points/: index_chunks() is the sole entry point, owning
payload construction, batched/bounded-concurrency upserts
(upsert_concurrency semaphore), and a soft-delete sweep for points a
shorter re-ingestion leaves behind. The sweep runs only after every upsert
in the attempt succeeds, so a failed attempt can leave a stale prefix but
never removes content from a working index.
- PointStorage port (application/ports/) + QdrantPointStorage adapter
(infrastructure/qdrant/points.py), keeping the qdrant_client SDK out of
application code per ADR-0015.
- FakePointStorage test double for exercising the ordering/idempotency
guarantees without a real Qdrant.
