Denial of Service in danny-avila/librechat

LibreChat version 0.7.9 is vulnerable to a Denial of Service (DoS) attack due to unbounded parameter values in the `/api/memories` endpoint. The `key` and `value` parameters accept arbitrarily large inputs without proper validation, leading to a null pointer error in the Rust-based backend when excessively large values are submitted. This results in the inability to create new memories, impacting the stability of the service.