Add permission step to onboarding

[anchpop]

This PR adds an onboarding step on MacOS that explicitly asks the user to grant permissions. Once permissions are granted, it automatically moves on to the next screen. It also fixes a bug where the app would crash if it did not have the necessary permissions, by removing input::EnigoState::new().expect("...");

CleanShot.2026-01-06.at.22.00.25.mp4

The most important architectural change is that input::EnigoState::new() is longer be called from initialize_core_logic, because this triggers a permission prompt, and I wanted the permission prompt not to appear until after the user clicked a "grant permission" button. (I didn't put too much thought into phrasing – "open settings" might be better, but a permission prompt does appear first.)

See discussion in #544

[anchpop]

Looked over the code, I think it's ready for review now.

I experienced a bug during testing where the app got stuck in the "loading" state according to the model selector, and transcriptions didn't work. It happened on the second open (e.g. open → onboard → close → open → stuck in "loading"). Unfortunately I stopped being able to reproduce it, and I'm not sure if it's related to my changes or a coincidence.

[cjpais]

Okay, thank you for this. I'll take a look soon, but give me maybe a week or two. I'm quite busy right now, but I do wanna bring this in for sure.

[anchpop]

Oh yeah, probably a good call on the translations haha. I forgot about that. Does the code need to be updated to use them?

[cjpais]

Should help to fix #564

[anchpop]

@cjpais I can confirm that this PR fixed #564 on my machine (when I tested it)! The crash was caused by this line:

fn initialize_core_logic(app_handle: &AppHandle) {
    let enigo_state = input::EnigoState::new().expect("Failed to initialize input state (Enigo)"); // ← crash!
    // [...]
}

[cjpais]

Thanks yea, I was unable to replicate the crash on my machine even toggling the permission off