mesh-delivery-assigner: compose nothing; judge proposals with its own judge and compare the published compositions

ADR 0593 §7, §8: the check's composition, its compose asks to the Go build seat and the state
compositions go (the checker asks the engines); a proposal is judged without frombus; mesh-wants.upgrade
compare reads every node's composed-<node> through mesh-host.composed. The assigner no longer imports
compose, composer, frombus or buildrun.

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

modules/mesh-delivery-assigner/module.json

@@ -24,22 +24,17 @@
     }
   ],
   "reads": [
-    "mesh-build-go.steps",
-    "mesh-config.kept",
-    "mesh-config.resolved",
-    "mesh-delivery-builder.build-log",
     "mesh-delivery-builder.builds",
-    "mesh-delivery-indexer.candidates",
     "mesh-delivery-indexer.manifests",
     "mesh-delivery-indexer.modules",
     "mesh-delivery-teller.answers",
     "mesh-delivery-watchman.presence",
     "mesh-grants.grants",
+    "mesh-host.composed",
     "mesh-provisioner.provisions",
     "node-engine.have"
   ],
   "uses": [
-    "node-build-go",
     "operator-channel"
   ],
   "invokes": [
@@ -63,7 +58,6 @@
     { "name": "candidates", "history": 5 },
     { "name": "pulses", "key-ttl": true },
     { "name": "asks", "history": 5 },
-    { "name": "compositions", "history": 5 },
     { "name": "differences", "history": 64 },
     { "name": "puts", "history": 20 },
     { "name": "wants", "history": 20 },