readonly mode for .sketch files

[devel0]

As a feature request, would helpful to have ability to enable readonly mode for files in the .sketch folder opened during debug session to avoid unadvertitely editing them having to redo the same on the real file ( note that readonly should apply only for the editor not the filesystem itself where arduino compiler need write during build )

this could be a general extension, may a .vscode/settings.json like the follow where if a filepath starts with given readonly inclusion matcher its got prevented from accidental editing

{
  "fs.readonly": [
    "${workspaceFolder}/.build"
  ]
}