chore: make vector extension optional for migrations

migrations/20240521092310_collab_embeddings.sql

@@ -1,3 +1,5 @@
+DO $$
+BEGIN
     -- Add migration script here
     CREATE EXTENSION IF NOT EXISTS vector;
 
@@ -15,3 +17,8 @@ CREATE TABLE IF NOT EXISTS af_collab_embeddings
     );
 
     CREATE INDEX IF NOT EXISTS af_collab_embeddings_similarity_idx ON af_collab_embeddings USING hnsw (embedding vector_cosine_ops);
+
+EXCEPTION WHEN OTHERS THEN
+    RAISE NOTICE 'could not create "vector" extension, ignoring this migration';
+END;
+$$ LANGUAGE plpgsql;