fix(NcModal): temporary deactivate focus-traps on modal open

[Antreesy]

☑️ Resolves

• Ref NcAppNavigation in mobile state blocks interacting with dialogs #5385
• add example of NcAppNavigation to the docs

Test cases:

Normal (works fine)	Mobile (has issues)

Important

1. Navigation footer: Button to open Modal:
   works correctly from keyboard and mouse click ✅

Important

2. Navigation header: Actions -> ActionButton (single button, don't force menu):
after closing the modal (with ESC) focus jumps to header input for a second, then to ActionButton
keyboard and mouse works fine ✅

Important

3. Navigation header: Actions -> ActionButton (close after click):
can't focus input, focus trap is inside NcAppNavigation 🐞

Important

4. Navigation header: Actions -> ActionButton (handle only click):
after mouse click on button, then on input -> focus jumps to header input 🐞
keyboard works fine

🖼️ Screenshots

🏚️ Before

Screencast.from.18.07.2024.11.30.24.webm

🏡 After

Screencast.from.18.07.2024.11.31.39.webm

🚧 Tasks

• Bring examples to common ground with docs: Fix NcAppNavigationCaption examples #5820

🏁 Checklist

• ⛑️ Tests are included or are not applicable
• 📘 Component documentation has been extended, updated or is not applicable
• 3️⃣ Backport to next requested with a Vue 3 upgrade

[Antreesy]

Referred to the library demo and other examples in vue-lib
Don't know what I can break with it, so waiting on expert review

[susnux]

@Antreesy we need to backport, right?

[Antreesy]

/backport to next