fix(quick-261005-blw): Links in Notiz-Kacheln oeffnen in neuem Tab

NoteLink ersetzt <a> der Markdown-Vorschau: target=_blank,
rel=noopener noreferrer; #-Sprungmarken bleiben im Fenster.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

apps/web/src/components/dashboard/widgets/note-task-list.test.tsx

@@ -3,7 +3,7 @@ import userEvent from '@testing-library/user-event';
 import { describe, expect, it, vi } from 'vitest';
 import MDEditor from '@uiw/react-md-editor';
 import rehypeSanitize from 'rehype-sanitize';
-import { NoteCheckbox, isTaskLine, toggleTaskLine } from './note-task-list';
+import { NoteCheckbox, NoteLink, isTaskLine, toggleTaskLine } from './note-task-list';
 
 describe('note-task-list', () => {
   describe('isTaskLine', () => {
@@ -143,5 +143,30 @@ describe('note-task-list', () => {
       expect((boxes[2] as HTMLInputElement).checked).toBe(true);
       expect((boxes[3] as HTMLInputElement).checked).toBe(false);
     });
+
+    it('oeffnet Links in einem neuen Tab, Sprungmarken im selben Fenster', () => {
+      const SRC =
+        '[Doku](https://example.com/doku) und https://example.org\n\n[oben](#oben)';
+
+      const { container } = render(
+        <MDEditor.Markdown
+          source={SRC}
+          rehypePlugins={[[rehypeSanitize]]}
+          components={{ a: NoteLink }}
+        />,
+      );
+
+      const doku = container.querySelector('a[href="https://example.com/doku"]');
+      const auto = container.querySelector('a[href="https://example.org"]');
+      const hash = container.querySelector('a[href="#oben"]');
+
+      for (const link of [doku, auto]) {
+        expect(link?.getAttribute('target')).toBe('_blank');
+        expect(link?.getAttribute('rel')).toBe('noopener noreferrer');
+        expect(link?.hasAttribute('node')).toBe(false);
+      }
+      expect(hash).not.toBeNull();
+      expect(hash?.hasAttribute('target')).toBe(false);
+    });
   });
 });