feat(ui): Review-Merge-Button — Claude nimmt Waiting-for-Review pro Liste ab

Neuer Button in der virtuellen Review-Liste: öffnet das Merge-Helper-Auswahlmodal
im Review-Modus (alle WaitingForReview-Tasks repo-verknüpfter Listen, gruppiert
unter Listen-Headern, alle vorgetickt) und startet pro gewählter Liste eine
ConPTY-Handler-Session direkt in der Merge-Phase — via bestehendem Handoff-Spec
(nextPhase "merge"), kein Triage/Wait davor. Handler-Host-Task wie beim vollen
"Let Claude handle it"-Lauf (HandlerBaseCommit, IsManual).

src/ClaudeDo.Ui/Views/Islands/TasksIslandView.axaml

@@ -39,6 +39,10 @@
                   Command="{Binding LetClaudeHandleCommand}" ToolTip.Tip="{loc:Tr tasks.letClaudeTip}">
             <PathIcon Width="15" Height="15" Data="{StaticResource Icon.AgentSuggested}"/>
           </Button>
+          <Button Classes="icon-btn" IsVisible="{Binding IsMergeReviewsVisible}"
+                  Command="{Binding MergeReviewsCommand}" ToolTip.Tip="{loc:Tr tasks.mergeReviewsTip}">
+            <PathIcon Width="15" Height="15" Data="{StaticResource Icon.GitBranch}"/>
+          </Button>
           <Button Classes="icon-btn" IsVisible="{Binding IsQuickClaudeVisible}"
                   Command="{Binding OpenQuickClaudeSessionCommand}" ToolTip.Tip="{loc:Tr tasks.quickClaudeTip}">
             <PathIcon Width="15" Height="15" Data="{StaticResource Icon.ArrowOut}"/>

src/ClaudeDo.Ui/Views/Modals/MergeHelperSelectionModal.axaml

@@ -53,6 +53,10 @@
             <ItemsControl.ItemTemplate>
               <DataTemplate DataType="vm:MergeHelperTaskRowViewModel">
                 <Grid ColumnDefinitions="24,32,*,120" Margin="0,1">
+                  <!-- Review mode: non-selectable list-name section header -->
+                  <TextBlock Grid.Column="0" Grid.ColumnSpan="3" Classes="eyebrow"
+                             Text="{Binding Title}" IsVisible="{Binding IsListHeader}"
+                             Margin="0,10,0,2" VerticalAlignment="Center"/>
                   <!-- Indent track for children, matching the task list's parent/child rendering -->
                   <Border Grid.Column="0" Width="24" IsVisible="{Binding IsChild}" VerticalAlignment="Stretch">
                     <Rectangle Width="1" Fill="{DynamicResource LineBrush}"
@@ -60,8 +64,10 @@
                   </Border>
                   <CheckBox Grid.Column="1" MinWidth="0"
                             IsChecked="{Binding IsSelected, Mode=TwoWay}"
+                            IsVisible="{Binding !IsListHeader}"
                             VerticalAlignment="Center"/>
                   <StackPanel Grid.Column="2" Orientation="Horizontal" Spacing="4"
+                              IsVisible="{Binding !IsListHeader}"
                               VerticalAlignment="Center">
                     <TextBlock Classes="body" Text="{Binding Title}"
                                VerticalAlignment="Center" Margin="4,0,0,0"
@@ -73,6 +79,7 @@
                     </Border>
                   </StackPanel>
                   <Border Grid.Column="3" Classes="chip"
+                          IsVisible="{Binding !IsListHeader}"
                           HorizontalAlignment="Left" VerticalAlignment="Center">
                     <TextBlock Text="{Binding StatusText}"/>
                   </Border>