Add missing root module dependencies

[piotrfila]

Right now it's a bit cumbersome to use one of microzig's modules - you have to clone the repo locally or add it as a git submodule and import it by path.

This PR exports all the modules in the root build.zig.

I'm not sure if updating all of microzig to import modules through the root project is a good idea - if we leave the imports as they are (by path) it's easier to override them for development (with zig command line options).

Also, I still need to find a good way to re-export libraries, not just modules

[mattnite]

I chatted to a friend outside the project about this, and ultimately I think we need to return to creating tarballs, but generating them far more often (like every push to main). This gets us the lazy dependencies and the standalone modules. It's either that or we contribute package manager features to Zig.

[piotrfila]

@mattnite Is this what you have in mind?