Capture mesh-catalog at feat/r4g (2246ccc4) with the templates its manifests name and its predefined.json, and lay the copy out as a repository's root

The catalogue's manifests moved their content into template files and fall back to predefined keys, so a copy of
module.json alone no longer passes the catalogue's own check; the bus's Dockerfile is gone from the catalogue.

testdata/beside/mesh-catalog/modules/mongodb/module.json.captured

@@ -81,22 +81,26 @@
       "id": "state",
       "type": "directory",
       "mode": "0700",
-      "place": "."
+      "place": ".",
+      "unknown": "program"
     },
     {
       "id": "grants",
       "type": "directory",
-      "mode": "0700"
+      "mode": "0700",
+      "unknown": "program"
     },
     {
       "id": "data",
       "type": "directory",
-      "mode": "0700"
+      "mode": "0700",
+      "unknown": "program"
     },
     {
       "id": "dumps",
       "type": "directory",
-      "mode": "0700"
+      "mode": "0700",
+      "unknown": "program"
     },
     {
       "id": "net",
@@ -109,7 +113,7 @@
       "path": "${dir:state}/server-root.secret",
       "mode": "0400",
       "owner": "999:999",
-      "content": "${secret:root}"
+      "template": "files/server-root.secret"
     },
     {
       "id": "server",
@@ -155,6 +159,11 @@
           "MESH_PROVISION_PASSWORD_FILE": "${dir:state}/root.secret",
           "MESH_RECEIVES": "${dir:grants}/mesh.json"
         }
+      },
+      {
+        "name": "files",
+        "kind": "archive",
+        "from": "files"
       }
     ]
   }