Feature request: expose the WebContainer API from a StackBlitz VM

[effulgentsia]

First of all, StackBlitz and WebContainer are both super cool! Thank you for them.

The StackBlitz VM API is quite limited. Issues #9, #15, and #19 are examples of missing capabilities. The WebContainer API covers these capabilities and more.

It would be incredibly useful to be able to control a StackBlitz embed with the WebContainer API. For example, to be able to run a process with something like vm.webContainer.spawn(...).

Is something like this on the roadmap?