Improve env building (not always automatic).

[fabioz]

Do you think it makes more sense to not build an env automatically until you decide to run the bot?

Just in a run may be a bit hard (because until changes are applied you won't have code-completion for the changed libraries and could have errors in code analysis due to that).

I think it could be something as manual command to rebuild + rebuild on run or maybe something as a pop-up when a change is detected and then the user can click that to do the rebuild.

[fabioz]

Note: this same issue is being used for the use case of forcing a build at a given time without waiting for the automatic build to kick in.

[kariharju]

This issue has been moved here, under Sema4AI/vscode-extension repository.