feat(ST-1136): mobile Settings-pagina + LogoutButton (T-325/T-326/T-327)

- app/(mobile)/m/settings/page.tsx — read-only account-info, product-selector
  (hergebruikt ActivateProductButton + setActiveProductAction met redirectTo
  /m/products/[id]/solo), QR-pairing-instructie, logout
- components/mobile/logout-button.tsx — AlertDialog "Uitloggen?" met bevestig
  + annuleer; demo-user mag uitloggen (geen demo-block)
- Tests: LogoutButton render + open + bevestig (logoutAction) + annuleer

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

__tests__/components/mobile/logout-button.test.tsx

@@ -0,0 +1,46 @@
+// @vitest-environment jsdom
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { render, screen, fireEvent, waitFor } from '@testing-library/react'
+
+const { logoutMock } = vi.hoisted(() => ({
+  logoutMock: vi.fn().mockResolvedValue(undefined),
+}))
+vi.mock('@/actions/auth', () => ({ logoutAction: logoutMock }))
+
+import { LogoutButton } from '@/components/mobile/logout-button'
+
+beforeEach(() => {
+  logoutMock.mockClear()
+})
+
+describe('LogoutButton', () => {
+  it('toont initieel alleen de Uitloggen-knop, geen dialog', () => {
+    render(<LogoutButton />)
+    expect(screen.getByRole('button', { name: /Uitloggen/ })).toBeTruthy()
+    expect(screen.queryByText(/Weet je zeker/)).toBeNull()
+  })
+
+  it('opent AlertDialog bij klikken op de knop', () => {
+    render(<LogoutButton />)
+    fireEvent.click(screen.getByRole('button', { name: /Uitloggen/ }))
+    expect(screen.getByText('Uitloggen?')).toBeTruthy()
+    expect(screen.getByText(/Weet je zeker/)).toBeTruthy()
+  })
+
+  it('roept logoutAction aan op bevestigen', async () => {
+    const { container } = render(<LogoutButton />)
+    fireEvent.click(screen.getByRole('button', { name: /Uitloggen/ }))
+    // Het body-portal wordt buiten container gerenderd; query op document.body.
+    const allButtons = Array.from(document.body.querySelectorAll('button'))
+    const confirmBtn = allButtons.find(b => b.textContent?.trim() === 'Uitloggen' && !container.contains(b)) ?? allButtons[allButtons.length - 1]
+    fireEvent.click(confirmBtn)
+    await waitFor(() => expect(logoutMock).toHaveBeenCalledTimes(1))
+  })
+
+  it('roept logoutAction NIET aan bij annuleren', () => {
+    render(<LogoutButton />)
+    fireEvent.click(screen.getByRole('button', { name: /Uitloggen/ }))
+    fireEvent.click(screen.getByText('Annuleren'))
+    expect(logoutMock).not.toHaveBeenCalled()
+  })
+})