Include wasm based installation as a fallback option.

I am using arm linux and arm windows versions of the moonbit tooling but installing it requires non-standard installation.
The blogpost here: https://www.moonbitlang.com/blog/moonbit-wasm-toolchain speaks to a method of installing the moonbit toolchain in these environments by using the following installation script (or following the instructions outlined):

```
curl -fsSL https://raw.githubusercontent.com/moonbitlang/moonbit-compiler/refs/heads/main/install.ts | node
```

It would be really awesome if moonup could incorporate this launch option.