The node-engine owns the composition it alone runs (H1, H2)

ADR 0593 §1 and §7: compose, its bus reader and runtime reader, takein,
validate, the overlay generator, the composer's run and mesh-compose, and
the judgement of a move leave mesh-sdk for the node-engine's internal
packages, so no other module composes and a change to them rebuilds only
the node-engine. The shapes others read (the composer's request and
verdict, the overlay's names, compositions and answers) stay in mesh-sdk.
The node's grant is now a golden file of what the grants part composes,
since the composer of the bus's user list leaves mesh-sdk too.

Claude-Session: https://claude.ai/code/session_01NcbgfJ9Gum47zkFKWRaovL

cmd/mesh-compose/testdata/mesh-catalog/modules/sshd/module.json.captured

@@ -0,0 +1,54 @@
+{
+  "module": "sshd",
+  "version": "1",
+  "upgrade": {
+    "policy": "record",
+    "why": "the operator's way into the machine when the mesh cannot reach it: a build that breaks it is found only when that way is needed, which no gate sees (hq ADR 0236)"
+  },
+  "capabilities": [
+    "package-manager",
+    "service-manager"
+  ],
+  "listens": [
+    {
+      "name": "ssh",
+      "port": 22,
+      "protocol": "tcp",
+      "from": "anywhere",
+      "why": "the operator's own door. From anywhere because the machines that need it are exactly the ones not on the mesh yet \u2014 and locking the operator out is the one failure a firewall must never arrange"
+    }
+  ],
+  "resources": [
+    {
+      "id": "package",
+      "type": "package",
+      "package": "openssh"
+    },
+    {
+      "id": "config",
+      "type": "file",
+      "path": "/etc/ssh/sshd_config.d/10-mesh.conf",
+      "mode": "0644",
+      "template": "files/10-mesh.conf"
+    },
+    {
+      "id": "run",
+      "type": "service",
+      "unit": "sshd.service",
+      "state": "running",
+      "boot": "enabled",
+      "restart-on": [
+        "config"
+      ]
+    }
+  ],
+  "build": {
+    "artifacts": [
+      {
+        "name": "files",
+        "kind": "archive",
+        "from": "files"
+      }
+    ]
+  }
+}