ux: style for current branch in branch tree (#991）

Signed-off-by: leo <longshuang@msn.cn>

Author: love-linger

src/ViewModels/BranchTreeNode.cs

@@ -40,9 +40,9 @@ public bool IsBranch
             get => Backend is Models.Branch;
         }
 
-        public FontWeight NameFontWeight
+        public bool IsCurrent
         {
-            get => Backend is Models.Branch { IsCurrent: true } ? FontWeight.Bold : FontWeight.Regular;
+            get => Backend is Models.Branch { IsCurrent: true };
         }
 
         public string Tooltip

src/Views/BranchTree.axaml

@@ -57,11 +57,17 @@
                                   IsExpanded="{Binding IsExpanded}"/>
 
             <!-- Name -->
-            <TextBlock Grid.Column="1"
-                       Text="{Binding Name}"
-                       Classes="primary"
-                       FontWeight="{Binding NameFontWeight}"
-                       TextTrimming="CharacterEllipsis"/>
+            <Grid Grid.Column="1" ColumnDefinitions="Auto,*">
+              <Border Grid.Column="0" Margin="0,0,4,0" Background="Green" Height="16" CornerRadius="8" VerticalAlignment="Center" IsVisible="{Binding IsCurrent}">
+                <TextBlock Text="HEAD" Classes="primary" Margin="8,0" Foreground="#FFDDDDDD" FontSize="10" VerticalAlignment="Center"/>
+              </Border>              
+              
+              <TextBlock Grid.Column="1"
+                         Classes="primary"
+                         Text="{Binding Name}"
+                         TextTrimming="CharacterEllipsis"/>
+            </Grid>
+            
 
             <!-- Tracking status -->
             <v:BranchTreeNodeTrackStatusPresenter Grid.Column="2"