Fix settings popup process alive

[ddoemonn]

Closes #39786

Release Notes:

• Fixed: Settings popup no longer keeps the process alive when closing Zed on Windows

[ddoemonn]

Sorry, there is a little bit of a mess in commits here. I haven't used Windows in years.

[JosephTLyons]

Thanks for the PR @ddoemonn - we'll check it out.

[Anthony-Eid]

Right now your PR closes the settings window when the workspace that originally opened it is closed. This doesn't cover the edge case where a user has multiple open workspaces.

I think it would be better if the subscription you created did something like this

let Some(app_state) = workspace::AppState::global(cx).upgrade() else {
    return;
};

if app_state.workspace_store.read(cx).workspaces().is_empty() {
// Close settings ui window
}

I'm happy to make the changes if you don't have the time too! Also, this way you won't need to add the subscription as a field on SettingsWindow, you could just detach it.

[ddoemonn]

Actually @Anthony-Eid if that works for you I wanna make the changes if you can give me little bit time. But of course I do not know it is urgent or not.

[Anthony-Eid]

@ddoemonn No worries! It's semi urgent because I want this to be apart of the stable settings ui release, so If you can make the changes by Monday that would be great. Otherwise, I can do it

[ddoemonn]

@Anthony-Eid Monday works for me. Thanks! I will try to be quick.