Intermediate, fixes a lot of update problems, keeping selection in place when updating planets still broken.

Stars Assistant/Views/BuColView.axaml

@@ -10,11 +10,12 @@
 
   <DataGrid x:Name="PlanetsGrid"
     ItemsSource="{Binding PlayerPlanets}"
+    SelectedItem="{Binding SelectedPlanet}"
     GridLinesVisibility="All"
     FrozenColumnCount="1"
-    
     BorderThickness="1" BorderBrush="Gray">
-    <DataGrid.Columns>
+      
+      <DataGrid.Columns>
         <DataGridTextColumn Header="Planet" Binding="{Binding Name}" />
         <!-- Class -->
         <!-- Info -->