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

internal/bootstrap/verify.go

@@ -13,14 +13,14 @@ import (
 //
 // A path rather than a shell command, because the image is `FROM scratch` and holds one static
 // binary and nothing else — no shell to invoke, nothing to interpret a command line
-// (mesh-control's Dockerfile, novox/hq ADR 0006). That is a property of the image this installer
+// (mesh-controller's Dockerfile, novox/hq ADR 0006). That is a property of the image this installer
 // carries, which is why the path can be written down here.
-const controlPlaneBinary = "/mesh-control"
+const controlPlaneBinary = "/mesh-controller"
 
 // answerEvery is how often the control plane is asked again while it is starting.
 var answerEvery = 2 * time.Second
 
-// Verified is what the substrate was found to be.
+// Verified is what the foundation was found to be.
 type Verified struct {
 	// Running is every long-running container the bundle declares, confirmed up.
 	Running []string
@@ -29,7 +29,7 @@ type Verified struct {
 	Answered string
 }
 
-// Verify proves the substrate is up and the control plane replies.
+// Verify proves the foundation is up and the control plane replies.
 //
 // **A container that is up is not a control plane that replies**, and this project has paid for
 // that distinction more than once: a runtime reports a container running from the moment the
@@ -146,7 +146,7 @@ func containerRunning(ctx context.Context, run Runner, probe time.Duration, name
 //
 // A run-once step has exited by design and a scheduled step has deliberately never been started
 // (novox/hq ADR 0052, ADR 0053), so asking either of them to be running would be asking the
-// substrate to be something other than what it declared.
+// foundation to be something other than what it declared.
 func longRunning(d *declaration.Declaration) []string {
 	var names []string
 	for _, r := range d.Resources {