Investigate WebAssembly (`browser-wasm`) support

[alexrp]

Zig has some support for WebAssembly, but I'm not sure how complete/usable it is.

This will depend on: dotnet/runtime#44636

It will also partially depend on:

• Explore static library support (for e.g. iOS) #9

[alexrp]

In theory, we should just be able to provide a .bc/.a file to the Blazor SDK once everything is in place. But things may get messy if Zig targets a different WASI version than Blazor...