[tunnel/app] Alert user if their tunnel is not active
I imagine a workflow like this:
BASIC
- User creates basic account.
- User launches Librem Tunnel and enters credentials.
- User attempts to connect.
- User receives message "This account does not have a tunnel service."
COMPLETE (INACTIVE)
- User creates complete account. Tunnel is inactive by default.
- User launches Librem Tunnel and enters credentials.
- User attempts to connect.
- User receives message "Tunnel service is not active. Please visit your profile to activate it."
COMPLETE (ACTIVE)
- User creates complete account. Tunnel is inactive by default.
- User activates tunnel.
- User launches Librem Tunnel and enters credentials.
- User attempts to connect.
- It works.
Suggested solution:
- A REST endpoint that returns a status of "unavailable", "inactive" or "active".
- App logic to match.