Verify with the browser adapter before initiating link prefetching

[jayohms]

This resolves an issue found in the Hotwire Native iOS library. See: hotwired/hotwire-native-ios#12

Link prefetching is being triggered on link taps on iOS, which has unintended consequences in the Hotwire Native iOS library. This causes double GET requests when crossing the default and modal context session boundaries, which use separate WKWebView instances.

Additionally, some urls correspond to natively implemented screens, not webviews, so link prefetching is undesirable for these cases, too.

This change allows the Hotwire Native libraries to have control of the link prefetching behavior. We will disable link prefetching in the native libraries where link hovering is not available.

Here are the corresponding Hotwire Native iOS and Hotwire Native Android PRs:

• Disable link prefetching via the turbo js adapter to prevent double-visit requests hotwire-native-ios#62
• Disable link prefetching to match the new behavior on iOS hotwire-native-android#78