test(frontend): task dialog, sharing avatars, trash, API key scopes, passwords (FLAW-19)

Covers opening and closing the task dialog (the former hook-order bug),
date/time fields and the view-only mode for viewer lists, the avatar
stack of shared items, the two-tap delete in the trash, scope selection
and badges of API keys, and the shared password rule.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/src/lib/__tests__/password.test.ts

@@ -0,0 +1,11 @@
+import { describe, it, expect } from 'vitest';
+import { passwordProblem } from '../password';
+
+describe('passwordProblem (same rule as the server)', () => {
+  it('needs 8 characters, counted as characters', () => {
+    expect(passwordProblem('kurz')).toMatch(/mindestens 8 Zeichen/);
+    expect(passwordProblem('        ')).toMatch(/mindestens 8 Zeichen/);
+    expect(passwordProblem('geheim12')).toBeNull();
+    expect(passwordProblem('äöüßäöüß')).toBeNull();
+  });
+});