CLI tool to debug and benchmark RAG retrieval without LLM calls.

- `ragtune explain "query"` → see what was retrieved with scores - `ragtune simulate` → batch eval with recall/MRR metrics - `ragtune compare` → compare embedders or chunk sizes - CI/CD mode for quality gates

Works with Qdrant, pgvector, Weaviate, Chroma, Pinecone.

Built because I kept guessing why retrieval was bad. Now I can see exactly what's happening.