Live-checked docker_stacks.yml directly. Total/dockerfile-strategy
counts (41/36) and the pinned_manual holdouts were already accurate.
But docker-socket-proxy and kodi's mariadb service were wrongly listed
as still hitting Docker Hub directly - both actually float a :latest
pull against a dedicated in-fleet mirror stack (docker-socket-proxy-
mirror, mariadb-latest) built via the normal dockerfile pattern. Fixed
the table and documented the real mechanism. Same gap existed in the
KB note, fixed there too.