* Rename TypeDefinitionProvider to TypeImeplementationProvider

**bug**
In #18346, I originally called the new go to implementation provider api `ImplementationProvider` which we then decided to rename to `TypeDefinitionProvider`. At the time, I didn't realize that a type definition was actually its own, unrelated concept.

**Fix**
Rename `TypeDefinitionProvider` to `TypeImplementationProvider` to make it clear what the purpose and use of this api is.

* Fix a few names in comments

Adds an initial implementation of scroll synrconization from the markdown preview to the editor. When the preview is scrolled, automatically scrolls the editor to reveal the same location.

This required adding a new supported reveal type `AtTop` in our API. This is already supported and used internally, but not really exposed in the public apis (except for the `revealLine` command).

* Add Go To Implementation Api

For #10806

Adds a new API for supporting  `go to implementation` command for languages. Implements an example for TS

* Rename

* Cleanup

* Add CompletionItemKind.Folder

Fixes #17435

Adds a new completion item kind for folder/directories. This is useful for path intellisense

For the icons, I copied the icons for folders into the suggestion icon set. Let me know if new ones are needed instead.

* Fix monaco.d.ts