Exclude CVS directories

Contains link fixes

This brings in new link handler code to support ctrl/cmd links

Adds enhanced security settings for the markdown preview. The new flow disable all scripts within the preview itself. Users can enable scripts on a per workspace basis.

When a markdown document that uses scripts is loaded, a warning is shown inside the document itself. This warning triggers a new security selector quick pick which allows users to enable or disable enahanced security in the workspace.

* Add resintall message when bundled tsserver.js is missing. Fixes #21689

* Use common wording for error

* Update warning message

fixes #21762

fixes #20142 #19242 #21833