This is a tweak to the wasm build, that expects the `geth_io` namespace
to expect a `geth_io` module, providing a `len` and `read` methods. This
will be provided by the WASM interface in sp1. This forces an API change
on the OpenVM side, but the interface on their side is still being
designed, so we should proceed with this change, and we'll make a
different tag for OpenVM if this can't work for them.
Co-authored-by: wakabat <wakabat@protonmail.com>
