This reverts commit 94c4b25a.

* 🐛 include setext heading levels

* 📝 typo

* 💚 use `===`

Fixes #30414

* show progress indicator for implementation cmd #31666

* Move progressService to DefinitionAction

Integrate native module for WindowsShellHelper

Make tree view data providers disposable
On main tree views disposed
- Deregister and dispose data providers

Implement smooth scrolling feature

* adopt the classifier;