[CHNL-13251] dismiss webview on border tap

[ab1470]

Description

This PR adds a tap target on the IAM webview's background so that the user can dismiss the IAM when the tap on the background.

The code in this PR only adds the tap target; actually handling the dismissal will come in a later PR, after we've implemented the architecture for displaying the IAM within the host app.

This addresses CHNL-13251.

Check List

• Are you changing anything with the public API?
• Have you tested this change on real device?
• Are your changes backwards compatible with previous SDK Versions?
• Have you added unit test coverage for your changes?
• Have you verified that your changes are compatible with all the operating system version this SDK currently supports?

Supporting Materials

This video shows the "tapped dismiss" message being printed to the console when the user taps on the background behind the web view.

Screen.Recording.2024-10-29.at.17.25.44.mov

[ab1470]

Closing this PR as we've decided on a different approach for MVP. We can revisit this at a future date if necessary.