feat(icons): add Lucide icon foundation

Add @lucide/angular dependency and a single shared entry point for
every icon in the app: app-icon (src/app/shared/ui/icon), backed by a
canonical name -> Lucide-icon registry (icon-registry.ts) covering
every concept the RC icon audit needs across storefront, builder, and
backoffice. One name per meaning, one default size/stroke-width, so
every screen renders the same icon the same way.

Package note: lucide-angular (unscoped) is deprecated upstream in
favor of @lucide/angular - installed the maintained package directly.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

package.json

@@ -30,6 +30,7 @@
     "@angular/platform-browser": "21.1.5",
     "@angular/router": "21.1.5",
     "@angular/service-worker": "21.1.5",
+    "@lucide/angular": "^1.25.0",
     "primeicons": "^7.0.0",
     "primeng": "^21.0.3",
     "rxjs": "~7.8.0",