fix: auto-resolve focus trap stack, if was changed outside of controller

[Antreesy]

☑️ Resolves

• Follow-up to fix(NcModal): correctly handle when trying to activate non-existing focus-trap #7084
  • NcModal is working fine with default trap stack, so there's no need for useTrapStackControl
• To be backported with [stable8] fix(NcModal): use useTrapStackControl for pausing other focus traps #7085
  • Does not change behaviour for main / Vue 3
  • Fixes following scenario for Vue 2:
    • Talk app -> shrink to mobile -> NcAppNavigation creates trap 0 -> trap 0 is active
    • open NcActions next to search bar -> pause trap 0
    • select 'Create open conversation' -> starts to mount NcModal
    • NcModal mounted -> useFocusTrap() -> creates trap 1 -> trap 1 is active
    • NcActions with close-after-click is closed -> unpause pausedStack (it has only [trap 0] from first step) -> trap 0 unpauses
    • trap 0 activates - trap 1 is paused -> focus trap is now in NcAppNavigation instead of NcModal
  • If trap stack was modified outside of stackcontroller, it should be safe to assume, that user action lead to that, and it's currently correctly resolved

🖼️ Screenshots

🏚️ Before (Vue 2 at #7085)

2025-08-12_12h39_00.mp4

🏡 After (Vue 2)

2025-08-12_12h34_55.mp4

🏁 Checklist

• ⛑️ Tests are included or are not applicable
• 📘 Component documentation has been extended, updated or is not applicable
• 2️⃣ Backport to stable8 for maintained Vue 2 version or not applicable

[susnux]

Code makes sense to me

[susnux]

this one can be backported to fix the stable8 issue, right?

[ShGKme]

Can you add an explanation here? Why we only need to unpause if the length is the same

[Antreesy]

It's the opposite of what is already written, do we need additional explanation here? I currently don't see how it could be expanded, please, advise

[susnux]

Maybe just align with code?

Suggested change

	* If the actual stack is different from the paused one, there were changes
	* outside of this controller, so we assume it's self-regulated and do not unpause.
	* Only if the actual stack is the same as the paused one, there were no changes
	* outside of this controller, so we can save assume it's not self-regulated and we need to unpause.

But I also think the current comment is already explaining it well

[Antreesy]

Will put PR description into composable comment, so devs can read and act from there at least. As it's not blocking, we should be able to follow-up with better explanation

[susnux]

/backport to stable8