Move building code out of src

[jeluard]

End-user code and code used to generate bindings are currently mixed in src. Similarly, required dependencies are added to the same module.

Find a way to separate both so that only the end user code is bundled, and no extra dependencies are leaked downstream.

[matthewkeil]

A best effort was made to support this. There are a couple more items that need to be handled in upcoming PR.

• Remove ts-node from deps (used for running scripts/install.ts)

[philknows]

No longer relevant after napi-rs refactor. Closing.