Issue number: resolves #31332

What is the current behavior?

Currently, pulling down inside a sheet or card modal dismisses the modal instead of triggering the refresher when the content uses a custom scroll host.

What is the new behavior?

With this change, the gesture resolves the refresher from the enclosing ion-content when the swipe target is a custom scroll host, so pulling down runs the refresher and leaves the modal alone. The new findRefresherInContent util only reports a refresher for the scroll host that refresher actually scrolls with, which is the first one in the content, so a second unrelated scroll host still swipes the modal normally. The expandToScroll: false path now runs the same check.

Does this introduce a breaking change?

Other information

Test coverage is 4 e2e tests on the new page:

Test page (iOS)
Test page (MD)

Current dev build:

8.8.18-dev.11786385944.17aca7e5