Huge console output turns UI unresponsive.

I guess just a random project with verbosity set to `Diagnostic` will render enough output to make the task runner explorer unresponsive and unable to cancel the execution.

Start by reproducing the issue in the Cake Visual Studio extension with a project configured for Diagnostic verbosity and enough output to make the task runner explorer unresponsive. Trace the console-output handling used by the task runner explorer and define done as keeping the UI responsive and allowing execution to be cancelled during large output bursts.

Written by the indexing model from the issue text.