Caterpillar

As of yesterday, the cleanup I had been working on for the last few weeks is finished! When I ported the game and the Caterpillar runtime to the browser, I relied on some heavy dependencies from the Rust ecosystem to do so. Now those are gone.

I replaced these heavy dependencies with purpose-built code, which ended up much simpler. This already enabled a change that wouldn't have been possible before (as best I can tell), running the runtime and the debugger in different WebAssembly modules. And it should make many other future changes possible (or at least easier).

Now I can finally work on re-introducing interactive programming. It's the central premise of Caterpillar, after all. I ignored it for a while, to focus on less explored aspects of the project. But now it's time to bring it back.