Name the two modules after their software: nftables and distribution

A module's identity is the software it is (ADR 0040). Two were named after the
job instead, and the job already had a name.

firewall installs the nftables package and runs nftables.service. The seat it
claims is the-packet-filter, which is correctly named for the role. Calling the
module firewall named neither the software nor the provision, and promised that
any firewall could sit there — the false genericity the naming rule forbids.

registry runs Distribution, the OCI reference implementation, and provides
artifact-store. So registry was a third name for a thing that already had two,
which is how one word ended up meaning the module, the software and the concept
in the same paragraph.

The capability stays firewall, and correctly: a capability IS a functionality, so
a node having one and fail2ban requiring one are both right. Only the module
moves.

Claude-Session: https://claude.ai/code/session_01D6qtiYU3P9jk3pnAXyAFyx

modules/distribution/module.json

@@ -0,0 +1,58 @@
+{
+  "module": "distribution",
+  "version": "1",
+  "provides": [
+    {
+      "name": "artifact-store",
+      "scope": "mesh"
+    }
+  ],
+  "claims": [
+    {
+      "name": "the-artifact-store",
+      "scope": "node"
+    }
+  ],
+  "capabilities": [
+    "container-runtime"
+  ],
+  "emits": [
+    "module.registry.image.pushed"
+  ],
+  "own-secrets": {
+    "broker": "/var/lib/mesh/registry/broker"
+  },
+  "serves": {
+    "artifact-store": {
+      "port": 5000
+    }
+  },
+  "listens": [
+    {
+      "port": 5000,
+      "protocol": "tcp",
+      "from": "mesh",
+      "why": "every machine pulls images and artifacts from here"
+    }
+  ],
+  "resources": [
+    {
+      "id": "state",
+      "type": "directory",
+      "path": "/var/lib/mesh/registry",
+      "mode": "0700"
+    },
+    {
+      "id": "store",
+      "type": "container",
+      "name": "mesh-registry",
+      "image": "registry@sha256:a3d8aaa63ed8681a604f1dea0aa03f100d5895b6a58ace528858a7b332415373",
+      "ports": [
+        "5000:5000"
+      ],
+      "volumes": [
+        "mesh-registry-data:/var/lib/registry"
+      ]
+    }
+  ]
+}