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/piscina/dist/common.d.ts

@@ -0,0 +1,30 @@
+import type { Histogram } from 'node:perf_hooks';
+import type { HistogramSummary } from './types';
+export declare const READY = "_WORKER_READY";
+/**
+ * True if the object implements the Transferable interface
+ *
+ * @export
+ * @param {unknown} value
+ * @return {*}  {boolean}
+ */
+export declare function isTransferable(value: unknown): boolean;
+/**
+ * True if object implements Transferable and has been returned
+ * by the Piscina.move() function
+ *
+ * TODO: narrow down the type of value
+ * @export
+ * @param {(unknown & PiscinaMovable)} value
+ * @return {*}  {boolean}
+ */
+export declare function isMovable(value: any): boolean;
+export declare function markMovable(value: {}): void;
+export declare const commonState: {
+    isWorkerThread: boolean;
+    workerData: undefined;
+};
+export declare function createHistogramSummary(histogram: Histogram): HistogramSummary;
+export declare function toHistogramIntegerNano(milliseconds: number): number;
+export declare function maybeFileURLToPath(filename: string): string;
+export declare function getAvailableParallelism(): number;