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/npm-normalize-package-bin/README.md

@@ -0,0 +1,14 @@
+# npm-normalize-package-bin
+
+Turn any flavor of allowable package.json bin into a normalized object.
+
+## API
+
+```js
+const normalize = require('npm-normalize-package-bin')
+const pkg = {name: 'foo', bin: 'bar'}
+console.log(normalize(pkg)) // {name:'foo', bin:{foo: 'bar'}}
+```
+
+Also strips out weird dots and slashes to prevent accidental and/or
+malicious bad behavior when the package is installed.