Add support for broadcast push notifications, channels

[eliperkins]

Is your feature request related to a problem? Please describe.

iOS 18 introduces a new method for sending push notifications to groups for Live Activities, called "broadcast push notifications." It'd be great to support this new APNS API with this library!

Describe the solution you'd like

• Creating, reading and deleting a broadcast channel with this package
• Sending broadcast push notifications to a channel with this package

Describe alternatives you've considered

Either using previous Live Activity APIs with push notifications, or not supporting this API all together.

Additional context

I'd be happy to implement support for this. Feel free to assign this issue to me.

[kylebrowning]

@eliperkins feel free to take this one up, otherwise ill get to it soon.

[kylebrowning]

@eliperkins one question, do you mind if it only works on swift-6? IM contemplating managing a version of swift 5 for a little while.

[eliperkins]

@kylebrowning sounds good! I started on a spike of this for an hour or so after creating this issue: main...eliperkins:APNSwift:channels

I've got some personal commitments in the next few weeks, so please take this across the finish line if you're interested in it!

one question, do you mind if it only works on swift-6? IM contemplating managing a version of swift 5 for a little while.

Swift 6 is all good with me 😇

[mattes-bru]

👍 Can't wait to test this out