feat(ios): iOS 13 supports system-wide font installation, apparently. So we should do that.

TIL: we can install fonts in iOS 13 and later without the messy provisioning profiles we have used in the past.
* https://developer.apple.com/documentation/coretext/3227897-ctfontmanagerregisterfonturls?language=objc (wonderful documentation, Apple!)
* https://stackoverflow.com/questions/58510316/apple-developer-what-is-the-fonts-capability-under-register-an-app-id-for
* https://stackoverflow.com/questions/57653398/ios-13-custom-fonts-download-and-installation
* https://developer.apple.com/videos/play/wwdc2019/227/ has more detail apparently
* http://codeworkshop.net/objc-diff/sdkdiffs/ios/13.0/CoreText.html

**Product context**
- OS: iOS 13