Pull the image build seat's asks beside the tools, at most the node's capacity (issue 1887 A3image, ADR 0525 §2-§6)

modules/mesh-build-image/module.json

@@ -11,6 +11,21 @@
     "keys",
     "steps"
   ],
+  "claims": [
+    {
+      "name": "node-build-image",
+      "scope": "node",
+      "serves": ["current", "pause", "resume"]
+    }
+  ],
+  "config": {
+    "capacity": {
+      "type": "string",
+      "description": "How many asks of the image build seat this module runs at once on each node, as node=asks pairs separated by commas, such as shanks=3,ace=2 (novox/hq ADR 0525 §5); a node set to 0 pulls nothing, a node not named runs one at a time. The control-node and the laptop build nothing.",
+      "pattern": "|[a-z0-9_-]+=[0-9]+(,[a-z0-9_-]+=[0-9]+)*",
+      "default": "shanks=3,ace=2,g14=0,novox=0"
+    }
+  },
   "tools": [
     "build_image_fetch",
     "build_image_build",
@@ -54,6 +69,17 @@
       "place": ".",
       "unknown": "program"
     },
+    {
+      "id": "settings",
+      "trusted": false,
+      "type": "file",
+      "path": "${dir:state}/settings.json",
+      "mode": "0600",
+      "owner": "mesh-build-image",
+      "takes-config": ["capacity"],
+      "merge": "json",
+      "template": "files/settings.json"
+    },
     {
       "id": "work",
       "type": "directory",