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/@jsonjoy.com/json-pointer/lib/get.js

@@ -0,0 +1,33 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.get = void 0;
+const hasOwnProperty_1 = require("@jsonjoy.com/util/lib/hasOwnProperty");
+const get = (val, path) => {
+    const pathLength = path.length;
+    let key;
+    if (!pathLength)
+        return val;
+    for (let i = 0; i < pathLength; i++) {
+        key = path[i];
+        if (val instanceof Array) {
+            if (typeof key !== 'number') {
+                if (key === '-')
+                    return undefined;
+                const key2 = ~~key;
+                if ('' + key2 !== key)
+                    return undefined;
+                key = key2;
+            }
+            val = val[key];
+        }
+        else if (typeof val === 'object') {
+            if (!val || !(0, hasOwnProperty_1.hasOwnProperty)(val, key))
+                return undefined;
+            val = val[key];
+        }
+        else
+            return undefined;
+    }
+    return val;
+};
+exports.get = get;