Document tips for using UnityDataTool with Library AssetDatabase artifacts

The AssetDatabase uses binary serialized files to represent imported Assets.

UnityDataTool can read such files, e.g. the dump command and can be a nicer alternative to the older binary2text tool that is typically used for this case.

It should only be necessary to look in these files in quite advanced cases. But it could be useful when developing custom scripted importers, or education about how Unity works, or for tracking a problem through the full pipeline from source to build output (e.g. for FBX files, or Scenes)

The Import Activity window shows Artifacts and has a "Show in Explorer" option for retrieving that artifact as a file. This is worth describing. We should also show how to do this from script (if possible using public APIs?)

Note: There are some changes in how these artifacts represented in recent versions of Unity, e.g. introduction of Unity Data Store (UDS) so the topic may have make information conditional on the version of Unity.

This task is to offer some

Start with UnityDataTool's dump command and the Import Activity window's "Show in Explorer" workflow. Verify whether public scripting APIs can retrieve artifacts and account for version differences such as Unity Data Store; the documentation is done when it explains artifact access, relevant use cases, and those caveats.