Io.netty/netty-codec-memcache: netty: memcache binary codec signed/unsigned type mismatch causes frame desynchronization and response smuggling

A flaw was found in io.netty/netty-codec-memcache. The Memcache binary protocol codec incorrectly reads `keyLength` and `extrasLength` as signed Java types instead of unsigned, as specified by the protocol. A malicious Memcache server can exploit this type mismatch by sending a specially crafted response. This can lead to frame desynchronization and response smuggling, where one client's data may be inadvertently exposed to another client's response stream in proxy or cache environments.