A definition names no host path for its own data

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).

modules/cloudflare-dns/module.json

@@ -12,13 +12,13 @@
     "public-dns": {}
   },
   "grants": {
-    "public-dns": "/var/lib/cloudflare-dns/grants"
+    "public-dns": "${dir:grants}"
   },
   "receives": {
-    "public-dns": "/var/lib/cloudflare-dns/grants/mesh.json"
+    "public-dns": "${dir:grants}/mesh.json"
   },
   "own-secrets": {
-    "token": "/var/lib/cloudflare-dns/token",
+    "token": "${dir:state}/token",
     "broker": "/var/lib/mesh/cloudflare-dns/broker"
   },
   "emits": [
@@ -35,19 +35,18 @@
     {
       "id": "state",
       "type": "directory",
-      "path": "/var/lib/cloudflare-dns",
-      "mode": "0700"
+      "mode": "0700",
+      "place": "."
     },
     {
       "id": "grants",
       "type": "directory",
-      "path": "/var/lib/cloudflare-dns/grants",
       "mode": "0700"
     },
     {
       "id": "config",
       "type": "file",
-      "path": "/var/lib/cloudflare-dns/config.json",
+      "path": "${dir:state}/config.json",
       "merge": "json",
       "content": "{}",
       "mode": "0600"
@@ -58,9 +57,9 @@
       "name": "mesh-cloudflare-dns",
       "network": "host",
       "volumes": [
-        "/var/lib/cloudflare-dns/config.json:/run/config/config.json:ro",
-        "/var/lib/cloudflare-dns/grants:/grants",
-        "/var/lib/cloudflare-dns/token:/run/secrets/token:ro",
+        "${dir:state}/config.json:/run/config/config.json:ro",
+        "${dir:grants}:/grants",
+        "${dir:state}/token:/run/secrets/token:ro",
         "/var/lib/mesh/cloudflare-dns/broker:/run/secrets/broker:ro"
       ],
       "env": {