Eliminate wasm-pack from build system

[Keavon]

We are using wasm-pack and wasm-pack-plugin as dev dependencies. But we really should only need wasm-bindgen. The fewer dependencies, the better— especially because wasm-pack is apparently unmaintained and has a high-severity security vulnerability from a sub-dependency and upgrading to the patched dependency version has gone unfixed for nearly half a year. We do not need all the features of wasm-pack, it simply rolls together the separate parts of our Vue (through webpack) and wasm-bindgen build process. Let's fix the security problem and work towards removing non-vital dependencies.

[Keavon]

After some research and attempts to figure this out, I've concluded that wasm-pack is truly the officially recommended approach and going without wasm-pack is likely to cause more problems than it solves. Hopefully somebody can fix the security vulnerability and otherwise continue maintaining it. I'll close this issue for now, but I'm still happy to accept pull requests to solve this anybody is familiar enough with the wasm-bindgen and webpack build systems to figure it out robustly. Another great use of time would be just going and fixing the security issue.