clarification node: converse for out-of-scope molecules / unavailable tasks; per-task availability; no-derivative matching

LLM intent router (agentic, robust naming) as primary; keyword only as fallback

v2: NL parsing + rich output + cached heavy tasks

CORS: allow *.vercel.app origins (prod alias + preview deploys)

ChemGraph Loop: guarded real-agent API (EMT/TBLite single-point energy)