Rebuild RAG: 32554 chunks, BM25 case-insensitive, price prefix

rebuild: drug-aware chunking 32554 chunks

Rebuild RAG: 34089 chunks, skip individual drug files, use consolidated DANH_MUC_THUOC_NOI_BO_TOAN_BO.md

Upload ChromaDB v3.0 - 37578 chunks

initial commit