Envoy Gateway: Wasm HTTP fetch decompresses gzip without output-size limit

Vulnerability report without repro case. Repro case may be added later after harness is complete. Preconditions 4: - Tenant can create EnvoyExtensionPolicy baseline - Attacker hosts a gzip-bomb at a reachable URL - sha256 unset optional field; check is post-decompression anyway - No operator...