Make it so when an embedding hasn't chagned, the metadata updated is.

The similarCards.last_updated flow requires cards to have their point updated every time the card.updated
timestamp updates. That updates more often than the embedding changes.

This makes it so the last_updated filter should work.

Part of #646. Part of #670.

functions/src/embeddings.ts

@@ -328,8 +328,22 @@ class EmbeddingStore {
 		}
 
 		if (existingPoint && existingPoint.payload && existingPoint.payload.content === text) {
-			//The embedding exists and is up to date, no need to do anything else.
-			console.log(`The embedding content had not changed for ${card.id} so stopping early`);
+			//The embedding exists and is up to date, no need to recompute the
+			//embedding. We do still want to update the timestamp in the vector
+			//store though, so in the future last_updated will note that it's
+			//current as of this moment, not when the embedding changed...
+			//because a card itself doesn't know the timestamp when the
+			//embeddable content last changed.
+			await this._qdrant.setPayload(QDRANT_COLLECTION_NAME, {
+				points: [
+					existingPoint.id
+				],
+				payload: {
+					last_updated: Date.now()
+				}
+			});
+
+			console.log(`Updated the metadata for ${card.id} because its embedding had not changed`);
 			return;
 		}
 

src/actions/similarity.ts

@@ -82,9 +82,6 @@ const similarCards = async (cardID : CardID, lastUpdated : MillisecondsSinceEpoc
 		};
 	}
 
-	//TODO: there's a massive problem with this flow currently... if a card is updated but
-	//doesn't have an embedding updated.
-
 	const request : SimilarCardsRequestData = {
 		card_id: cardID,
 		last_updated: lastUpdated