feat(11-06): add the tide fake Centrifugo recorder, broadcast goldens and parity:broadcasts

- CentrifugoRecorder records publish/broadcast requests (method, path,
  whether the API key matched, JSON body) and binds loopback only
- BroadcastGolden load/write, NormalizePublications (timestamps, actor,
  captured ids only) and DiffPublications (structural, key order ignored)
- RecordBroadcasts runs a flow or one step against a loopback backend
- summer parity:broadcasts wraps it; README documents format and rules

cmd/summer/main_test.go

@@ -19,7 +19,7 @@ func TestToolCommandNames(t *testing.T) {
 	for _, c := range toolCommands() {
 		names = append(names, c.Name)
 	}
-	for _, want := range []string{"build", "make:plugin", "make:model", "make:migration", "make:command", "make:job", "make:admin-controller", "plugin:add", "dev", "migrate", "migrate:rollback", "migrate:status", "serve", "queue:work", "queue:clear", "schedule:run"} {
+	for _, want := range []string{"build", "make:plugin", "make:model", "make:migration", "make:command", "make:job", "make:admin-controller", "plugin:add", "dev", "migrate", "migrate:rollback", "migrate:status", "serve", "queue:work", "queue:clear", "schedule:run", "parity:broadcasts"} {
 		if !slices.Contains(names, want) {
 			t.Fatalf("missing %s in %v", want, names)
 		}
@@ -33,6 +33,7 @@ func TestToolCommandNames(t *testing.T) {
 		"make:job":              {"[plugin] [name]"},
 		"make:admin-controller": {"[plugin] [name]"},
 		"schedule:run":          {"--once"},
+		"parity:broadcasts":     {"--flow", "--step", "--ids", "127.0.0.1:8424"},
 	}
 	for cmd, wants := range helpWants {
 		var buf bytes.Buffer