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/isexe/dist/commonjs/index.d.ts

@@ -0,0 +1,14 @@
+import * as posix from './posix.js';
+import * as win32 from './win32.js';
+export * from './options.js';
+export { win32, posix };
+/**
+ * Determine whether a path is executable on the current platform.
+ */
+export declare const isexe: (path: string, options?: import("./options.js").IsexeOptions) => Promise<boolean>;
+/**
+ * Synchronously determine whether a path is executable on the
+ * current platform.
+ */
+export declare const sync: (path: string, options?: import("./options.js").IsexeOptions) => boolean;
+//# sourceMappingURL=index.d.ts.map