For #88719

With this change, instead of passing custom editor edit json back and forth with the extension host, we keep the original edit objects on the extension host. This means that we can pass extensions back the exact same edit object they first hand to us. It also means that edits no longer need to be json serializable.

- extract a separate DocumentRangeSemanticTokensProvider that deals with a document range
- extract a separate provideDocumentSemanticTokensEdits that deals with updating via SemanticTokensEdits a previous result

Part of #81388

Part of #81388

Part of #81388

Part of #81388

Part of #81388

Part of https://github.com/microsoft/vscode-remote-release/issues/1777 and https://github.com/microsoft/vscode/issues/81388

fixes #83743

Fix #85722

* Fixes more node 12 typing errors

For #82514

* Remove Symbol.toStringTag usage for now

* Reverting a few fixes that are not comptible with current node typings

* Revert one more use of StringDecoder

Must wait until we actually pick up the new typings

If multiple instances of the same  custom editor are opened for the same resource, the edit stack should be shared between them. This matches how we work with text files