Search items and lists

Search the user's Roma workspace — their items (tasks, notes, the rows of every list they keep) and their lists, and what others shared with them (an item shared on its own, a list they joined and every item on it, each marked isSharedWithMe) — by meaning or keyword (hybrid semantic + keyword retrieval). Use this when the user asks about their own information, plans or anything they may have saved, and before adding something that may already exist. Their wording often won't match their notes' wording; the semantic arm bridges that gap (and across languages). Returns the best-matching passage per item, each with its list; get_item returns an item in full. An empty result means nothing relevant is saved. Not for general web knowledge.