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/go/module.json.captured

@@ -0,0 +1,20 @@
+{
+  "module": "go",
+  "version": "1",
+  "capabilities": [
+    "package-manager"
+  ],
+  "provides": [
+    {
+      "name": "go-toolchain",
+      "reach": "machine"
+    }
+  ],
+  "resources": [
+    {
+      "id": "go",
+      "type": "package",
+      "package": "go"
+    }
+  ]
+}