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/path-to-regexp/Readme.md

@@ -0,0 +1,35 @@
+# Path-to-RegExp
+
+Turn an Express-style path string such as `/user/:name` into a regular expression.
+
+**Note:** This is a legacy branch. You should upgrade to `1.x`.
+
+## Usage
+
+```javascript
+var pathToRegexp = require('path-to-regexp');
+```
+
+### pathToRegexp(path, keys, options)
+
+ - **path** A string in the express format, an array of such strings, or a regular expression
+ - **keys** An array to be populated with the keys present in the url.  Once the function completes, this will be an array of strings.
+ - **options**
+   - **options.sensitive** Defaults to false, set this to true to make routes case sensitive
+   - **options.strict** Defaults to false, set this to true to make the trailing slash matter.
+   - **options.end** Defaults to true, set this to false to only match the prefix of the URL.
+
+```javascript
+var keys = [];
+var exp = pathToRegexp('/foo/:bar', keys);
+//keys = ['bar']
+//exp = /^\/foo\/(?:([^\/]+?))\/?$/i
+```
+
+## Live Demo
+
+You can see a live demo of this library in use at [express-route-tester](http://forbeslindesay.github.com/express-route-tester/).
+
+## License
+
+  MIT