Seal the build agent the forge genesis raised, in place of the builder's npm-password (hq issue 121, ADR 0336)

The build agent declares neither the retired builder's npm-password own-secret
nor a serves setting, so the packages step handed its credential to nothing
and genesis's sdk step had no way to publish. The packages step now seals the
genesis-package-registry own-secret to build-agent: the forge on this node's
loopback, the port given for the package registry, its npm path, and the
mesh-builder account with its password. setFoundationSettings no longer gives
the builder a serves.port.

internal/bootstrap/builder_test.go

@@ -37,27 +37,6 @@ func recording(t *testing.T) (*controlRecorder, controlPlane) {
 	return c, controlPlane{container: "temp-mesh-controller", run: c.run, timeout: time.Second}
 }
 
-func TestTheBuildersPackageRegistryPortIsASettingAndNotTheManifest(t *testing.T) {
-	c, control := recording(t)
-	o := Options{Node: "anchor", Ports: FoundationPorts{Packages: 3100}, Wait: time.Second}
-	if _, err := installModule(context.Background(), o, control, BuilderModule,
-		[]byte(theBuildersBinding), quietly); err != nil {
-		t.Fatal(err)
-	}
-	if got := c.settings["builder-settings.json"]; got != `{"serves":{"port":3100}}` {
-		t.Errorf("the builder was told %q about the package registry's port", got)
-	}
-	// The manifest reaches the mesh as the catalogue wrote it. A port rewritten into it here is a
-	// port the next registration from the catalogue silently takes back.
-	if got := c.settings["builder-module.json"]; got != theBuildersBinding {
-		t.Errorf("the installer changed the builder's manifest:\n%s", got)
-	}
-	set, push := c.index("settings set builder"), c.index("push anchor")
-	if set < 0 || push < 0 || set > push {
-		t.Fatalf("the port was not set before the push that raises the builder: %v", c.told)
-	}
-}
-
 func TestTheBuilderOnTheDefaultPackagesPortIsToldNothing(t *testing.T) {
 	c, control := recording(t)
 	o := Options{Node: "anchor", Wait: time.Second}