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/fs-print/README.md

@@ -0,0 +1,55 @@
+# @jsonjoy.com/fs-print
+
+File system tree printer - print a file system structure as a tree.
+
+Provides a simple API to print any filesystem implementing the `FsSynchronousApi` interface
+as a formatted tree structure, useful for debugging and visualization.
+
+## Installation
+
+```bash
+npm install @jsonjoy.com/fs-print
+```
+
+## Usage
+
+```ts
+import { toTreeSync } from '@jsonjoy.com/fs-print';
+import { memfs } from 'memfs';
+
+const { fs } = memfs({
+  '/readme.md': '...',
+  '/src/index.ts': '...',
+  '/src/util.ts': '...',
+});
+
+console.log(toTreeSync(fs));
+```
+
+Output:
+
+```
+/
+├─ src/
+│  ├─ index.ts
+│  └─ util.ts
+└─ readme.md
+```
+
+## Options
+
+You can customize the output with options:
+
+```ts
+toTreeSync(fs, {
+  dir: '/src', // Starting directory (default: '/')
+  depth: 2, // Maximum depth to traverse (default: 10)
+  separator: '/', // Path separator (default: '/')
+  tab: '  ', // Indentation string (default: '')
+  sort: true, // Sort entries (default: true)
+});
+```
+
+## License
+
+Apache-2.0