feat: Capacitor support (`jaspr_native`?)

[lukehutch]

A killer feature for Jaspr would be to support building platform-native apps with Capacitor.

This could be packaged as "jaspr_native", à la React Native. It would make Jaspr a serious alternative to Ionic.

Typings by @jodinathan could be used to create typesafe Dart bindings from the Capacitor Typescript type definitions.

[schultek]

Anyone feel free to do this, but I won't. For many reasons, but mainly time.