feat(header): progreso de lectura y compactado al bajar

components/layout/__tests__/Header.test.tsx

@@ -14,4 +14,15 @@ describe('<Header />', () => {
     const cta = screen.getByRole('link', { name: /Hablemos/i });
     expect(cta).toHaveAttribute('href', '#contacto');
   });
+  it('shows reading progress', () => {
+    const { container } = render(<Header />);
+    expect(container.querySelector('.bg-dorado')).toBeInTheDocument();
+  });
+
+  it('starts roomy, before any scrolling has happened', () => {
+    const { container } = render(<Header />);
+    // The header compacts on scroll; at rest it must be in its tall state, or
+    // the wordmark would land already shrunken on first paint.
+    expect(container.querySelector('header')?.className).toContain('py-3');
+  });
 });