ragleap-rag v0.12.8

Fixed: ingest() now accepts an optional metadata: Optional[Dict] = None parameter, threaded through to ingest_text(). This closes a real, unexplained inconsistency - ingest_url() and ingest_image(), ingest()'s two siblings for raw-input ingestion, both already had this parameter; ingest() silently dropped it despite being arguably the most commonly used entry point (the one that does format auto-detection). Discovered downstream while fixing the identical gap in ragleap-tools' ingest_document tool (v0.1.1). Backward compatible - metadata defaults to None, no existing caller (including ragleap-graph) is affected. 2 new live tests against real Postgres. Full suite: 255 passed, 10 skipped.