ux(shell): Ctrl+N opens a second dialog over the welcome tour #1820

Problem

With the welcome tour open (modal), Ctrl+N still opens Select your database on top of it; the tour stays under it. The same global shortcuts fire under any modal dialog (Ctrl+N, probably Ctrl+P, F1, Ctrl+B).

Seen in a debug build (dev at 25c766c): tour open at step 1, press_key ctrl+n → two stacked dialogs.

Expected

A modal dialog blocks the app-level shortcuts, except the ones the dialog itself handles (Esc, F1 for the tour). Or at least Ctrl+N closes the tour first.

Where

The shortcut bindings of MainScreen / QueryaCommandHost (CallbackShortcuts above the Navigator) versus the tour's own CallbackShortcuts.