Propose a new visit for cross-origin redirects

[jayohms]

The core turbo.js library does not permit cross-origin visit requests (i.e. a link that redirects to an external domain). These requests call the adapter method visitRequestFailedWithStatusCode(visit, statusCode) for all platforms.

Similar to the turbo-android implementation, turbo-ios need adapter changes to support proposing new visits for cross-origin redirects. PR: hotwired/turbo-android#325