refactor: remove dependency on Avalonia.Controls.TreeDataGrid

Author: love-linger

src/App.axaml

@@ -20,7 +20,6 @@
   <Application.Styles>
     <FluentTheme />
     <StyleInclude Source="avares://Avalonia.Controls.DataGrid/Themes/Fluent.xaml"/>
-    <StyleInclude Source="avares://Avalonia.Controls.TreeDataGrid/Themes/Fluent.axaml"/>
     <StyleInclude Source="avares://AvaloniaEdit/Themes/Fluent/AvaloniaEdit.xaml" />
     <StyleInclude Source="/Resources/Styles.axaml"/>
   </Application.Styles>