It seems not consider row margins(space between rows)

[GF-Huang]

Describe the bug
When I drag the row to the space between rows, it will move to bottom of DataGrid.

To Reproduce
Steps to reproduce the behavior:

1. Drag the row to the space between rows.

Expected behavior
Move to the position between rows even if they have space.

Screenshots
https://github.com/user-attachments/assets/31364555-ae21-41a9-88ea-f3f0f9093e50

Desktop (please complete the following information):

• OS: Windows 11 24H2 26100.4652
• Version 4.0.0

Additional context
Add any other context about the problem here.

[CodingOctocat]

I've encountered the same issue: #512
My solution is quite simple:

<DataGrid.RowStyle>
    <Style BasedOn="{StaticResource DataGridRowStyle}"
           TargetType="{x:Type DataGridRow}">
        <Setter Property="Margin" Value="0" />
        <Setter Property="BorderThickness" Value="2" /> 💡BorderBrush default null
    </Style>
</DataGrid.RowStyle>