Does SQLite support some kind of monotonic transaction id that can be used as a cache coherency key? Say a client writes a new record to the database which returns `{"result": "ok", "transaction_id": 123}`, then to ensure that subsequent read requests are coherent they provide a header that checks that the read replica has transaction_id >= 123 and either waits for replication before serving or fails the request. (Perhaps a good use for the embedded worker?)