Wrong behavior when user without permissions views order Stripe section

[RobinTheHood]

When a staff member without the required permissions to view the Stripe overview opens an order in the admin panel (Admin > Orders > Show), the module currently loads the shop frontend homepage inside the Stripe placeholder.

This leads to two problems:

1. The frontend page is incorrectly embedded in the admin panel.
2. The frontend styles override admin styles, which breaks the layout and causes a completely distorted view.

See also: Forum discussion

Expected behavior:
Instead of embedding the frontend, the module should render a simple HTML message within the admin area (e.g., “You do not have permission to view the Stripe overview for this order”) without additional styles.

Steps to reproduce:

1. Create a user without permissions for the Stripe overview in order processing.
2. Log in with this user.
3. Go to Admin > Orders > Show.
4. Observe that the frontend homepage is loaded inside the Stripe placeholder and breaks the layout.

Environment:

• Stripe Module version: 0.13.0
• modified Shop version: 3.1.4
• Browser: Safari

Additional context:
This issue only occurs for users without the required permissions. For users with permissions, the Stripe overview loads as expected.