The first executable slice of ADR 0112 / to-be 27, sized to what the
operator settled tonight: a module definition names no host path for
its own data. A directory resource may omit path; composition resolves
it to <root>/<module>/<id>, the root a node's setting on Rendering with
/var/lib as the default — which reproduces exactly the layout novox
converged to by hand. ${dir:<id>} names the place from a resource's
path, content, mounts, environment and env-files, the same shape as
${bound:…}. A directory that states a path keeps it and still answers
by name — that is the adopted-data placement, mssql its live case.
Resolved in the controller at composition, so the wire format and the
host change not at all; a reference naming no directory refuses at the
manifest and again at composition; nested fills are rebuilt, never
written into the manifest's own maps, because one manifest composes
for many nodes.