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/catalogue-mqtt.yml

@@ -11,7 +11,7 @@
 # the broker — so "the broker came up" is itself the proof the seed ran, because an unseeded store
 # crash-loops the broker.
 #
-#   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-module-runtime.sh mosquitto builds mesh-runtime-mosquitto:development (carrying
 #   mosquitto_ctrl and the compiled bootstrap entrypoint) into the local daemon, which this scenario
 #   pulls from the internet over its uplink. eclipse-mosquitto:2 must be in the local
@@ -32,7 +32,7 @@ machines:
     cpus: 2
 
 images:
-  - mesh-control:development
+  - mesh-controller:development
   - mesh-runtime-mosquitto:development
 
 place: