Respect multi selection when Copy value in Watch Expression View

This reverts commit 99f0ab9f.

There was / is a typo in `markdownRenderer.js` that allowed any *trusted* document to pass arbitrary HTML through the marked.js sanitizer provided it is wrapped in `<span></span>` tags, or similar.

What could you have done with this? Not much that was not already possible in trusted mode, which, as far as I can tell is used just for Jypiter Notebooks that pretty much definitionally can execute Python anyway.

Insane strips everything worthwhile except `<a data-href=''/>` which you can use to send `command:` URIs on click (`javascript:` URIs are disabled at a higher level of abstraction), but are already whitelisted (L141) for trusted documents.

* Fix scrolling of markdown preview.

* Use scrollDisabledCount.

* Stop initializing scrollDisabledCount.

* Make scrollTo enough large to occur scroll events.

* Should resolve when the error event occurs.

For #109277

- Add `option` opener priority. This means the oper will only be shown if requested but will not replace the default opener
- Persist registered openers for IntelliSense suggestions

* move home menu into compact menu

* add web app icon to titlebar

* add TODO

#92038

* Codespaces, setup and beginner journeys for getting started.

* Added missing alt texts and shortened some texts.

* Fixing wording for terminal in Codespaces.

* Fixed action for opening settings

* Replacing unoptimized PNGs with optimized jpgs (70% compression)

* Add some minor css tweaks
Co-authored-by: NJackson Kearl <jakearl@microsoft.com>