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/p-limit/index.d.ts

@@ -0,0 +1,40 @@
+/* eslint-disable @typescript-eslint/member-ordering */
+
+export interface LimitFunction {
+	/**
+	The number of promises that are currently running.
+	*/
+	readonly activeCount: number;
+
+	/**
+	The number of promises that are waiting to run (i.e. their internal `fn` was not called yet).
+	*/
+	readonly pendingCount: number;
+
+	/**
+	Discard pending promises that are waiting to run.
+
+	This might be useful if you want to teardown the queue at the end of your program's lifecycle or discard any function calls referencing an intermediary state of your app.
+
+	Note: This does not cancel promises that are already running.
+	*/
+	clearQueue: () => void;
+
+	/**
+	@param fn - Promise-returning/async function.
+	@param arguments - Any arguments to pass through to `fn`. Support for passing arguments on to the `fn` is provided in order to be able to avoid creating unnecessary closures. You probably don't need this optimization unless you're pushing a lot of functions.
+	@returns The promise returned by calling `fn(...arguments)`.
+	*/
+	<Arguments extends unknown[], ReturnType>(
+		fn: (...arguments: Arguments) => PromiseLike<ReturnType> | ReturnType,
+		...arguments: Arguments
+	): Promise<ReturnType>;
+}
+
+/**
+Run multiple promise-returning & async functions with limited concurrency.
+
+@param concurrency - Concurrency limit. Minimum: `1`.
+@returns A `limit` function.
+*/
+export default function pLimit(concurrency: number): LimitFunction;