mesh-control: the control plane could not read its own connections

Its image is FROM scratch and runs as 65534. The host writes a sealed own-secret 0600,
owned by root, which is right — but the module then bind-mounted those three files into
the container and told the process to open them. It cannot:

  $ docker run --rm -v <0600 root file>:/run/secrets/inventory:ro \
      -e MESH_STORE_INVENTORY_FILE=/run/secrets/inventory mesh-control:development status
  MESH_STORE_INVENTORY_FILE names /run/secrets/inventory ... and it cannot be read:
  open /run/secrets/inventory: permission denied

Measured on a workstation, not reasoned about. Every other module in this catalogue gets
away with the same mount because its runtime container runs as root; this one does not,
and genesis (novox/hq ADR 0067) would have stopped at step 9 with a control-plane module
that starts and cannot open a context.

The connections go through the env file this module already has instead. That file is
mode 0600 and is read by the container runtime's client, which is root — the same reason
the broker's URL has always reached the process this way. It also sidesteps the inode
that a file bind mount pins (290be37, step-ca): --env-file is read afresh at create, and
restart-on names it.

The own-secrets stay exactly as they were, because the installer delivers the substrate's
real connection strings into them with `secret accept` before the first push — the mesh
did not make those credentials and cannot invent them.

Claude-Session: https://claude.ai/code/session_01LrgweAeERJYBg88c5cKDzF

modules/mesh-control/module.json

@@ -26,11 +26,11 @@
       "mode": "0700"
     },
     {
-      "id": "broker-env",
+      "id": "control-env",
       "type": "file",
-      "path": "/var/lib/mesh/mesh-control/broker.env",
+      "path": "/var/lib/mesh/mesh-control/control.env",
       "mode": "0600",
-      "content": "MESH_BROKER_AMQP=${secret:broker}\nMESH_BROKER_MANAGEMENT=${secret:broker-management}\nMESH_BROKER_ADDRESS=${machine:at}:5671\n"
+      "content": "MESH_STORE_INVENTORY=${secret:inventory}\nMESH_STORE_IDENTITY=${secret:identity}\nMESH_STORE_LICENCES=${secret:licences}\nMESH_BROKER_AMQP=${secret:broker}\nMESH_BROKER_MANAGEMENT=${secret:broker-management}\nMESH_BROKER_ADDRESS=${machine:at}:5671\n"
     },
     {
       "id": "server",
@@ -42,27 +42,16 @@
         "serve"
       ],
       "env-file": [
-        "/var/lib/mesh/mesh-control/broker.env"
+        "/var/lib/mesh/mesh-control/control.env"
       ],
       "env": {
-        "MESH_STORE_INVENTORY_FILE": "/run/secrets/inventory",
-        "MESH_STORE_IDENTITY_FILE": "/run/secrets/identity",
-        "MESH_STORE_LICENCES_FILE": "/run/secrets/licences",
         "MESH_BROKER_CERTIFICATE": "/broker-tls/tls.crt"
       },
       "volumes": [
-        "mesh-broker-tls:/broker-tls:ro",
-        "/var/lib/mesh/mesh-control/inventory:/run/secrets/inventory:ro",
-        "/var/lib/mesh/mesh-control/identity:/run/secrets/identity:ro",
-        "/var/lib/mesh/mesh-control/licences:/run/secrets/licences:ro"
+        "mesh-broker-tls:/broker-tls:ro"
       ],
       "restart-on": [
-        "needs-inventory",
-        "needs-identity",
-        "needs-licences",
-        "needs-broker",
-        "needs-broker-management",
-        "broker-env"
+        "control-env"
       ]
     }
   ]