No behaviour change: a pure move plus pub(crate) visibility. PrivRequest,
hive-priv-sock and every validation rule are untouched; the 58 tests move
next to the code they test, unchanged.
Why (#5476): the 28 root ops shared one 4.3k-line file, so no op family
could be reviewed on its own and every new root op landed there by default.
main.rs keeps the socket loop and the dispatch table. container (lifecycle),
container_config (nspawn flags, systemd drop-ins, daemon-reload), storage
(btrfs subvolumes, quotas, snapshots, du), files (pause marker, socket dir,
legacy tmpfiles) and infra (gateway nginx, forge admin, infra containers)
each carry their own validation; shared holds the agent-name checks, the
credential-name charset and StagedFile, plus the tests' scratch helpers
(one counter crate-wide, so test dirs stay unique).
hive-priv/README.md is in the diff because it named src/main.rs as the
home of container_flake_action and now describes the module layout.
6ac637c7e3