One bus: the runtime pins the certificate after the server speaks, and the old transport goes

Every module that dialled the new bus failed its handshake with "wrong version
number": the runtime pinned the server's certificate by a raw TLS connection to a
port on which the server speaks first, in the clear. The pin is taken after the
INFO line now, on the same socket, and then the real connection verifies against
exactly that certificate.

And the old transport is deleted — its client, its tests, its dependency — with
the wire-compatibility pins that only existed for the move (novox/hq ADR 0131,
design 28 task 5.5). A credential names the bus, and there is one.

package.json

@@ -14,11 +14,9 @@
   },
   "dependencies": {
     "@novox/mesh-sdk": "^0.1.0",
-    "amqplib": "^0.10.9",
     "nats": "^2.29.0"
   },
   "devDependencies": {
-    "@types/amqplib": "^0.10.8",
     "@types/node": "^22.20.1",
     "typescript": "^5.9.3"
   }