Investigate if we could use only VSCode public API's

During the POC, we used some VSCode internal APIs and did some monkey patching.

i.e. :
https://code.visualstudio.com/api/references/vscode-api#TextEditor - see hide() method
workbench.action.closeActiveEditor

The goal of this task is to revisit those places and check if we can achieve the same using only public APIs.