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/@yarnpkg/lockfile/README.md

@@ -0,0 +1,22 @@
+# yarn-lockfile
+
+Parse and/or write `yarn.lock` files
+
+## Usage Examples
+
+```js
+const fs = require('fs');
+const lockfile = require('@yarnpkg/lockfile');
+// or (es6)
+import fs from 'fs';
+import * as lockfile from '@yarnpkg/lockfile';
+
+let file = fs.readFileSync('yarn.lock', 'utf8');
+let json = lockfile.parse(file);
+
+console.log(json);
+
+let fileAgain = lockfile.stringify(json);
+
+console.log(fileAgain);
+```

node_modules/@yarnpkg/lockfile/package.json

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+{
+  "name": "@yarnpkg/lockfile",
+  "version": "1.1.0",
+  "description": "The parser/stringifier for Yarn lockfiles.",
+  "main": "index.js",
+  "repository": "https://github.com/yarnpkg/yarn/blob/master/packages/lockfile",
+  "keywords": [
+    "yarn",
+    "yarnpkg",
+    "lockfile",
+    "dependency",
+    "npm"
+  ],
+  "license": "BSD-2-Clause"
+}