automc: operator UI on AUTOMC_UI_BINDING

Adds a separate HTTP server (not the upstream API on :25590) for the
operator dashboard. Single-page UI with two panes:
  * routes table — current pg-synced mappings, polled every 2s
  * logs — SSE stream backed by a logrus hook + 500-entry ring buffer

Opt-in via AUTOMC_UI_BINDING (e.g. ":8082"); unset = no-op, behaves
exactly like upstream. Designed to live behind server-manager's
/infra/mc-router/* reverse-proxy.

Patch is internal/automc-only, same fork philosophy as the rest —
upstream files stay verbatim.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

internal/automc/wire.go

@@ -20,5 +20,14 @@ func Wire(ctx context.Context) error {
 	s := newSyncer(dsn, waker)
 	go s.run(ctx)
 	logrus.Info("automc: pg route sync started")
+
+	// Operator UI on a separate port — upstream's API_BINDING stays
+	// JSON-only and untouched. Enable by setting AUTOMC_UI_BINDING (e.g.
+	// ":8082"); leave unset to skip and behave exactly like upstream.
+	if uiBinding := os.Getenv("AUTOMC_UI_BINDING"); uiBinding != "" {
+		bus := NewLogBus(500)
+		logrus.AddHook(&logrusBusHook{bus: bus})
+		startUI(ctx, uiBinding, bus)
+	}
 	return nil
 }