* Use SuspendingObservableCollection
* updates
* Use thread-safe models
* handle loading
* fix up tekla
* remove option
* fix suspension
* Revit shouldn't register changed twice. top level goes to base class
* use suspension when loading
* forgot include
* lock saving like loading
* Remove public accessor
* Require a document store for each DUI usage
* simpify load and state saving since we don't need to observe the collection externally
* added back property for javascript UI
* fmt
* move progress handling to own classes
* fmt
* fmt
* fix up diff
* Fix merge
* adjust sending progress
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Co-authored-by: Oğuzhan Koral <45078678+oguzhankoral@users.noreply.github.com>
Adam Hathcock