Rename mesh-control -> mesh-controller, substrate -> foundation

One name per thing, per the HQ glossary: the module/container/image/binary/repo
becomes mesh-controller, the seat the-controller, and the store+broker pair the
foundation (embedded base bundles, default template and example lock renamed with
their go:embed directives). No behaviour change — a pure vocabulary rename.

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

scenarios/route-forwarding.yml

@@ -14,9 +14,9 @@
 # publicly-trusted certificate and answering an HTTP-01 challenge at the name — is proven separately
 # by certificates.test.ts against a real ACME server (Pebble), driving the same proxy binary.
 #
-#   MESH_LAB_HOST_BINARY=.../mesh-host   MESH_LAB_BUNDLE=.../examples/substrate-first-node.lock
+#   MESH_LAB_HOST_BINARY=.../mesh-host   MESH_LAB_BUNDLE=.../examples/foundation-first-node.lock
 #   scripts/build-route-proxy-image.sh builds mesh-route-proxy:development into the local daemon
-#   (from mesh-control/examples/route-proxy, via mesh-catalog/modules/route-proxy/Dockerfile).
+#   (from mesh-controller/examples/route-proxy, via mesh-catalog/modules/route-proxy/Dockerfile).
 #   alpine:latest must be in the local daemon — hello-web's backend is a bare alpine that serves a
 #   fixed page over a busybox nc loop. Both images are stocked and served by digest.
 scenario: route-forwarding
@@ -35,8 +35,8 @@ machines:
     cpus: 2
 
 images:
-  - mesh-control:development
-  # The route-proxy's image, built from the canonical Go proxy in mesh-control by
+  - mesh-controller:development
+  # The route-proxy's image, built from the canonical Go proxy in mesh-controller by
   # scripts/build-route-proxy-image.sh, and hello-web's backend, a bare alpine nc loop.
   - mesh-route-proxy:development