- Add Validator("VECTOR_SYNC_METRICS_REFRESH_INTERVAL", gte=1) so a 0/negative
value can't turn the publish loop into a busy-spin.
- Annotate count_indexed's qdrant_client param as AsyncQdrantClient.
- Add tests: exact kwarg is forwarded to qdrant count, and the placeholder
filter matches False (excludes placeholders) with chunk_index pinned to 0.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>