feat(ui): conflict resolver shows why Continue is disabled

Continue was already gated on CanContinue (all files resolved); surface a
footer hint counting the still-unresolved conflicts/files so the disabled
state is explained, not just for binary files.

src/ClaudeDo.Ui/Views/Conflicts/ConflictResolverView.axaml

@@ -67,7 +67,7 @@
         <TextBlock Grid.Column="0" Classes="meta" VerticalAlignment="Center"
                    Foreground="{DynamicResource BloodBrush}"
                    Text="{Binding ContinueHint}"
-                   IsVisible="{Binding HasBinaryFiles}"/>
+                   IsVisible="{Binding ContinueHint, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
         <StackPanel Grid.Column="1" Orientation="Horizontal" Spacing="8">
           <Button Classes="btn accent" Content="{loc:Tr conflictResolver.continue}"
                   Command="{Binding ContinueCommand}" IsEnabled="{Binding CanContinue}"/>