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/ajv/dist/compile/resolve.d.ts

@@ -0,0 +1,12 @@
+import type { AnySchema, AnySchemaObject, UriResolver } from "../types";
+import type Ajv from "../ajv";
+import type { URIComponent } from "fast-uri";
+export type LocalRefs = {
+    [Ref in string]?: AnySchemaObject;
+};
+export declare function inlineRef(schema: AnySchema, limit?: boolean | number): boolean;
+export declare function getFullPath(resolver: UriResolver, id?: string, normalize?: boolean): string;
+export declare function _getFullPath(resolver: UriResolver, p: URIComponent): string;
+export declare function normalizeId(id: string | undefined): string;
+export declare function resolveUrl(resolver: UriResolver, baseId: string, id: string): string;
+export declare function getSchemaRefs(this: Ajv, schema: AnySchema, baseId: string): LocalRefs;