feat(01-07): add SettingsView and wire into MainWindow Settings tab

- Create Views/Tabs/SettingsView.xaml (UserControl with language ComboBox en/fr, DataFolder TextBox and Browse button using TranslationSource)
- Create Views/Tabs/SettingsView.xaml.cs (DI constructor injection of SettingsViewModel, LoadAsync on Loaded)
- Update MainWindow.xaml to add xmlns:views namespace and clear placeholder TextBlock from SettingsTabItem
- Register SettingsView as Transient in DI; resolve and set as SettingsTabItem.Content from MainWindow constructor
- All 42 unit tests pass, 0 build errors

SharepointToolbox/MainWindow.xaml

@@ -5,6 +5,7 @@
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:loc="clr-namespace:SharepointToolbox.Localization"
         xmlns:controls="clr-namespace:SharepointToolbox.Views.Controls"
+        xmlns:views="clr-namespace:SharepointToolbox.Views.Tabs"
         mc:Ignorable="d"
         Title="{Binding Source={x:Static loc:TranslationSource.Instance}, Path=[app.title]}"
         MinWidth="900" MinHeight="600" Height="700" Width="1100">
@@ -61,10 +62,9 @@
       <TabItem Header="{Binding Source={x:Static loc:TranslationSource.Instance}, Path=[tab.structure]}">
         <controls:FeatureTabBase />
       </TabItem>
-      <!-- Settings tab: placeholder TextBlock replaced by SettingsView in plan 01-07 -->
+      <!-- Settings tab: content set from code-behind via DI-resolved SettingsView -->
       <TabItem x:Name="SettingsTabItem"
                Header="{Binding Source={x:Static loc:TranslationSource.Instance}, Path=[tab.settings]}">
-        <TextBlock Text="Settings (plan 01-07)" HorizontalAlignment="Center" VerticalAlignment="Center" />
       </TabItem>
     </TabControl>
   </DockPanel>

SharepointToolbox/Views/Tabs/SettingsView.xaml

@@ -0,0 +1,28 @@
+<UserControl x:Class="SharepointToolbox.Views.Tabs.SettingsView"
+             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:loc="clr-namespace:SharepointToolbox.Localization">
+  <StackPanel Margin="16">
+    <!-- Language -->
+    <Label Content="{Binding Source={x:Static loc:TranslationSource.Instance}, Path=[settings.language]}" />
+    <ComboBox Width="200" HorizontalAlignment="Left"
+              SelectedValue="{Binding SelectedLanguage}"
+              SelectedValuePath="Tag">
+      <ComboBoxItem Tag="en"
+                    Content="{Binding Source={x:Static loc:TranslationSource.Instance}, Path=[settings.lang.en]}" />
+      <ComboBoxItem Tag="fr"
+                    Content="{Binding Source={x:Static loc:TranslationSource.Instance}, Path=[settings.lang.fr]}" />
+    </ComboBox>
+
+    <Separator Margin="0,12" />
+
+    <!-- Data folder -->
+    <Label Content="{Binding Source={x:Static loc:TranslationSource.Instance}, Path=[settings.folder]}" />
+    <DockPanel>
+      <Button DockPanel.Dock="Right"
+              Content="{Binding Source={x:Static loc:TranslationSource.Instance}, Path=[settings.browse]}"
+              Command="{Binding BrowseFolderCommand}" Width="80" Margin="8,0,0,0" />
+      <TextBox Text="{Binding DataFolder, UpdateSourceTrigger=PropertyChanged}" />
+    </DockPanel>
+  </StackPanel>
+</UserControl>

SharepointToolbox/Views/Tabs/SettingsView.xaml.cs

@@ -0,0 +1,14 @@
+using System.Windows.Controls;
+using SharepointToolbox.ViewModels.Tabs;
+
+namespace SharepointToolbox.Views.Tabs;
+
+public partial class SettingsView : UserControl
+{
+    public SettingsView(SettingsViewModel viewModel)
+    {
+        InitializeComponent();
+        DataContext = viewModel;
+        Loaded += async (_, _) => await viewModel.LoadAsync();
+    }
+}