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/schedule-tick.yml

@@ -14,7 +14,7 @@
 #   - the container fires when the cron is due (top of the next minute);
 #   - it fires AGAIN on the following minute — recurrence, not a one-shot.
 #
-#   MESH_LAB_HOST_BINARY=.../mesh-host   MESH_LAB_MODULES=.../mesh-control/examples/modules
+#   MESH_LAB_HOST_BINARY=.../mesh-host   MESH_LAB_MODULES=.../mesh-controller/examples/modules
 #   alpine:latest must be in the local daemon; the machine pulls it from the internet over its
 #   uplink, and the scheduled container declares it exactly as the catalogue writes it.
 #   There is no runtime image: schedtest carries no code of its own — the scheduled container is a
@@ -35,7 +35,7 @@ machines:
     cpus: 2
 
 images:
-  - mesh-control:development
+  - mesh-controller:development
 
 place:
   # Only the host — schedtest has no mesh-runtime to place. The tick image is pulled from the