Support Width = * and Width = AUTO

[Bush-cat]

Is your feature request related to a problem? Please describe.
I used both with the Datagrid from CommunityToolkit.WinUI.UI.
Width = * made it use the full available space in the window, if you have two columns with Width = * they would each use half of the window
Width = Auto made the Column the samllest width it needed to fit the Text and Buttons

Describe the solution you'd like
Support both to work like other common controls as described above.

[uixiu]

Width="NaN" will auto resize the content column, but not the header column, which should be resized manually AFAIK.