Consider giving JavaScript host hooks to respond to rollbacks

[kettle11]

Tangle only syncs WebAssembly but to do anything useful it has to integrate with the host environment.

Tangle could expose some way for the host environment to respond to rollbacks.

A pontential solution could look something like this:

let imports = {
  createBuffer: () => {
    return context.createBuffer(); 
  }
};

let rollbacks = {
  createBuffer: (args, returnValue) => {
    context.deleteBuffer(returnValue);
  }
};

const result = await Tangle.instantiateStreaming(fetch("my_wasm.wasm"), imports, { rollbacks });

Then Tangle would have to track internally which import calls have rollbacks and when Tangle rolls back and resimulates it will call the appropriate rollback callbacks.

---

A bigger-picture solution might be some sort of meta-Tangle layer that connects individual Tangle nodes and standardizes how rollback events are passed between them. The JavaScript host could be seen as a 'node' that must be manually networked but it still abides by the same interface. Probably something like that is too big-picture to do soon but it's worth keeping in mind.