devverse-rag-chat

# DevVerse RAG And Chat Workflow 1. Preserve the response contract between backend and UI. The UI expects an `answer` string, a `sources` array, bracket citations in the answer body, and a trailing `Sources:` section that it strips before rendering. 2. Keep citation parsing aligned with UI behavior. If you change citation formatting, update both `lib/chat-citations.ts` and the chat UI in the same task. 3. Preserve hybrid retrieval unless you are intentionally redesigning it. `lib/rag.ts` merges Pinecone results with the local lexical fallback from `lib/rag-local.ts`. 4. Read the detailed contract before changing retrieval, prompt format, or vector metadata. @references/rag-contract.md 5. Assume Pinecone vectors are stale after article or chunking changes until vectorization is rerun. 6. Validate chat changes with both tests and manual reasoning about runtime behavior. Use `devverse-validate` for the automated part, then note any live env checks you could not perform.