standalone version for Extism interop?

[nilslice]

Howdy! I know its been mentioned in passing, but I figure an issue to track would be worth creating. I am curious if we could bridge language support here with Extism, and could leverage a standalone wasm build. I see there are some Emscripten imports0 fulfilled by JS APIs, e.g. env::emscripten_date_now, which would be possible to stub. Curious if you could point to any docs or build info on where to dig a little deeper?

Great work, very cool to see this :)