Use typed throws

[colemancda]

Also exports the error types as public API and removed an unused type.

[ktoso]

Thanks but we need to prepare this some more for future with source stability when making enums public

[colemancda]

Addressed feedback, let me know if any more changes are needed. My main use case is the JavaVirtualMachine.shared() call, but I wanted to make this change for all error throws so this can be part of the public API in the future, and downstream projects can catch the errors properly.