Feat: migrate to jni and jnigen

[orestesgaolin]

I would like to propose migrating this plugin to use JNI and JNIGen to query the package manager API. We could maintain backward compatibility with the public API by wrapping the Android methods, although they may become synchronous. We could also expose a low-level API to the package manager itself.

I've done a proof of concept here https://github.com/orestesgaolin/native_interop_presentation/tree/main/packagelist and the package manager can be pretty easily accessed via the bindings or Kotlin wrapper (e.g. https://github.com/orestesgaolin/native_interop_presentation/blob/659dc64b380c64e8005c349337951876b151ddc8/packagelist/lib/main.dart#L33 ).

Please let me know if you would be interested in receiving a pull request with the proposal.