feat: add Z12/Z13 bind APIs, stock import, and sync docs

Enable auto default sync channels on agent activate, bind-code/phone confirm flows, publish ALTER, and align admin/yuheng docs with the production bind path.

platform/internal/meta/store.go

@@ -140,6 +140,19 @@ func (s *MemoryStore) ListByTenant(_ context.Context, tenantID int64) ([]AppSumm
 	return out, nil
 }
 
+func (s *MemoryStore) ListPublishedApps(_ context.Context) ([]*AppRecord, error) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	out := make([]*AppRecord, 0)
+	for _, app := range s.apps {
+		if app == nil || app.Status != StatusPublished {
+			continue
+		}
+		out = append(out, cloneApp(app))
+	}
+	return out, nil
+}
+
 func summarizeApp(app *AppRecord) AppSummary {
 	sum := AppSummary{
 		AppID:        app.AppID,