Initial commit: notification-elements-demo app

Interactive Angular 19 demo for @sda/notification-elements-ui with
6 sections: Bell & Feed, Notification Center, Inbox, Comments &
Threads, Mention Input, and Full-Featured layout. Includes mock
data, dark mode toggle, and real-time event log.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

node_modules/@angular/build/builders.json

@@ -0,0 +1,29 @@
+{
+  "builders": {
+    "application": {
+      "implementation": "./src/builders/application/index",
+      "schema": "./src/builders/application/schema.json",
+      "description": "Build an application."
+    },
+    "dev-server": {
+      "implementation": "./src/builders/dev-server/index",
+      "schema": "./src/builders/dev-server/schema.json",
+      "description": "Execute a development server for an application."
+    },
+    "extract-i18n": {
+      "implementation": "./src/builders/extract-i18n/index",
+      "schema": "./src/builders/extract-i18n/schema.json",
+      "description": "Extract i18n messages from an application."
+    },
+    "karma": {
+      "implementation": "./src/builders/karma",
+      "schema": "./src/builders/karma/schema.json",
+      "description": "Run Karma unit tests."
+    },
+    "ng-packagr": {
+      "implementation": "./src/builders/ng-packagr/index",
+      "schema": "./src/builders/ng-packagr/schema.json",
+      "description": "Build a library with ng-packagr."
+    }
+  }
+}