fix(bottom-sheet-native): add change detection for bottom sheet dismissal

[Andries-Smit]

Bug: Bottom Sheet Doesn't Detect Cancellation by Outside Click

The custom bottom sheet component cannot be reliably used for editing workflows because it lacks the ability to detect when users cancel by clicking outside the sheet and bottom sheet is closing. This prevents developers from handling sheet dismissal and resetting form state accordingly.

Solution

Add an onChange event that triggers whenever the triggerAttribute updates. This enables parent components to detect cancellation and other state changes, making the bottom sheet suitable for editing scenarios.

The code changes is minor, as we only need to add the onChange property to the attribute and an action element, the triggering of the triggerAttributeChange will be handle by the pluggable widget framework when the triggerAttribute is changed on closing of the bottom sheet.

Impact

Enables editing workflows and improves component usability for state management.

[MxKevinBeqo]

Hello @Andries-Smit , thank you so much for the contributions 🙇 .
This one seems like it has been a long-running PR but it finally got addressed in this PR here as part of another ticket.

It is also included in 11.6 and 11.12 respective versions of the Native Mobile Resources.

[Andries-Smit]

@MxKevinBeqo thanks for the review. I appreciate you looking into this.

Please be aware PR #575 addresses a different issue—it fixes the bottom sheet not closing at all. This PR is about something else entirely.

The Actual Need:
We need to detect when the bottom sheet closes, specifically when the user dismisses it by clicking the overlay. Currently:

• ✓ Closing via nanoflow action works (we can attach workflows)
• ✗ Closing by overlay click has no event—we can't detect it or trigger any cancel logic

This PR adds an on-change event so we can listen for all dismissals, including overlay clicks, and handle cancellations properly in edit workflows.

They're solving different problems.