MCP Ruby SDK: Unbounded line buffer in stdio transports leads to memory exhaustion (DoS)

Summary The stdio transports in MCP::Server::Transports::StdioTransport and MCP::Client::Stdio read newline-delimited JSON-RPC frames using IOgets with no limit argument. CRuby's IOgets with no limit reads from the current position until the next separator \n with no upper bound on the returned...