feat(ui): My Day actions, orphan-aware grouping, menu restructure

Pending UI work:
- My Day add/remove context actions on task rows (parent removal cascades to children)
- orphan-aware grouping: a child whose parent isn't in view renders as a top-level row, not an indented draft
- shell menu restructure (Worker / Repositories submenus); 'Finalize plan' action, drop 'Queue subtasks sequentially'
- notes editor refinements
- subtask-row hover tweak (Surface3, no transition)
- bump Avalonia 12.0.0 -> 12.0.4

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

@@ -28,11 +28,8 @@
       <ItemsControl ItemsSource="{Binding Bullets}">
         <ItemsControl.ItemTemplate>
           <DataTemplate x:DataType="vm:NoteBulletViewModel">
-            <Grid ColumnDefinitions="*,Auto,Auto" Margin="0,2" ColumnSpacing="6">
-              <TextBox Grid.Column="0" Text="{Binding Text}"/>
-              <Button Grid.Column="1" Classes="btn" Content="{loc:Tr notes.save}" Command="{Binding SaveCommand}"/>
-              <Button Grid.Column="2" Classes="btn" Content="{loc:Tr notes.delete}" Command="{Binding DeleteCommand}"/>
-            </Grid>
+            <TextBox Text="{Binding Text}" Margin="0,2"
+                     LostFocus="OnBulletLostFocus"/>
           </DataTemplate>
         </ItemsControl.ItemTemplate>
       </ItemsControl>