refactor(tenant-router): import embed routes from @cio/utils

Replace the cross-package relative source import with the workspace
package subpath so embed routing uses the canonical constants module.

apps/tenant-router/src/embed-assets.ts

@@ -1,4 +1,4 @@
-import { EMBED_WIDGET_ROUTES } from '../../../packages/utils/src/constants/embeds';
+import { EMBED_WIDGET_ROUTES } from '@cio/utils/constants/embeds';
 
 const EMBED_CONTENT_TYPES: Record<string, string> = {
   html: 'text/html',