Twenty-eight modules' data directories are placed: the root as place ".", a sub-directory named by
its id, and every host-side reference — binds, secrets, own secrets, grants, receives, file paths,
mounts, env-files — as ${dir:<id>}. Resolved on the default root every path is the one the manifest
named before, which the controller's TestPlacedDirectoriesKeepTheirPaths proves over both checkouts;
so no data moves and no machine sees a change. Five directories whose id is not their last segment
keep their path as a placement (novox/hq issue 119, ADR 0112, design 27).