V3 bounded gzip inspection capability pack. By-value connector composition (service_kind=cli, no separate ingredient): one local gzip CLI ingredient exposes fixed operations for readiness, gzip stream integrity testing, compact gzip metadata listing, and verbose gzip metadata listing. The pack deliberately does not expose compression or decompression output because this gzip implementation writes compressed/decompressed bytes to stdout or mutates source-adjacent files; neither fits the current file-ref output contract without shell redirection. File operations accept one gzip path or materialized file_ref, capture only metadata or exit status, and expose no stdout payload bytes, source-adjacent writes, recursive mode, suffix override, force mode, original-name restore, arbitrary flags, caller-supplied environment override, stdin, output-file write, or shell wrapper. Requires gzip on PATH.