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/is-unicode-supported/readme.md

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+# is-unicode-supported
+
+> Detect whether the terminal supports Unicode
+
+This can be useful to decide whether to use Unicode characters or fallback ASCII characters in command-line output.
+
+Note that the check is quite naive. It just assumes all non-Windows terminals support Unicode and hard-codes which Windows terminals that do support Unicode. However, I have been using this logic in some popular packages for years without problems.
+
+## Install
+
+```
+$ npm install is-unicode-supported
+```
+
+## Usage
+
+```js
+const isUnicodeSupported = require('is-unicode-supported');
+
+isUnicodeSupported();
+//=> true
+```
+
+## API
+
+### isUnicodeSupported()
+
+Returns a `boolean` for whether the terminal supports Unicode.
+
+## Related
+
+- [is-interactive](https://github.com/sindresorhus/is-interactive) - Check if stdout or stderr is interactive
+- [supports-color](https://github.com/chalk/supports-color) - Detect whether a terminal supports color
+- [figures](https://github.com/sindresorhus/figures) - Unicode symbols with Windows fallbacks
+- [log-symbols](https://github.com/sindresorhus/log-symbols) - Colored symbols for various log levels