Display dialog if awatcher is missing on wayland

[0xbrayo]

If aw-tauri doesn't detect awatcher module and detects the wayland display environment, it should display a dialog explaining why awatcher is required on wayland and perhaps even open a link to the awatcher repo.

[ErikBjare]

Should it display dialog if any default modules for the system is missing? I think since we're shipping it in the main bundle this dialog may be unnecessary (rare case) and might be annoying during testing with no modules.