Raise genesis on the bus the mesh runs on, from one bundle (hq issue 146, ADR 0331)

The installer could not raise a first node: the old bundle's control plane had no
MESH_BUS_NATS and crash-looped, and the NATS bundle was refused because rootsecrets
only knew the previous broker's guest:guest@ template.

One bundle now, the NATS one. rootsecrets makes the controller's bus account and puts
it in both placeholders (the address and the bcrypt hash in the carried user list),
kept with its hash so a re-run writes the same bundle. Preflight refuses a template
naming no bus connection it knows, naming the placeholder, instead of waiting out the
verify step. The broker step adopts the bus as the nats module and refuses, by name,
a catalogue without it or a server that is not the foundation's container.

internal/bootstrap/bootstrap.go

@@ -503,7 +503,7 @@ func Run(ctx context.Context, o Options, d Deps, say func(string)) (Result, erro
 	for _, c := range []struct {
 		what, path string
 		made       bool
-	}{{"store superuser", StoreSuperuserFile, creds.StoreMade}, {"broker admin", BrokerAdminFile, creds.BrokerMade}} {
+	}{{"store superuser", StoreSuperuserFile, creds.StoreMade}, {"bus controller", BusControllerFile, creds.BusMade}} {
 		switch {
 		case c.made && o.DryRun:
 			say(fmt.Sprintf("  %-17s would be made and kept at %s (0600)", c.what, c.path))
@@ -513,9 +513,9 @@ func Run(ctx context.Context, o Options, d Deps, say func(string)) (Result, erro
 			say(fmt.Sprintf("  %-17s already at %s — kept", c.what, c.path))
 		}
 	}
-	say(fmt.Sprintf("  credentials       the template's bootstrap and guest are gone: %d store and %d broker "+
-		"connection(s) rewritten, the store reads its password from a file, the broker's admin is changed once it answers",
-		root.StoreURLs, root.BrokerURLs))
+	say(fmt.Sprintf("  credentials       the template's bootstrap is gone: %d store and %d bus "+
+		"connection(s) rewritten, the store reads its password from a file, the bus is raised with the controller's account",
+		root.StoreURLs, root.BusURLs))
 	if rewritten.Renamed {
 		say(fmt.Sprintf("  control plane     %s, renamed from %s",
 			rewritten.TempName, rewritten.WasCalled))
@@ -733,7 +733,7 @@ func Run(ctx context.Context, o Options, d Deps, say func(string)) (Result, erro
 	}
 
 	// ---- broker ---------------------------------------------------------------------------
-	say("broker — the foundation's broker, adopted as the lavinmq module: one bus, not two")
+	say("broker — the foundation's bus, adopted as the nats module: one bus, not two")
 	if err := InstallBroker(ctx, o, permanentControl, rewritten.Declaration, say); err != nil {
 		return result, failed(StepBroker, err)
 	}