feat(app): navbar restructure, contacts tab and address info window

- Reorder tabs: Storico / Invia / Ricevi / Indirizzi / Contatti
- Invia: ComboBox to quick-fill recipient from saved contacts
- Contatti: new tab to add/remove contacts (name + address), persisted
  to the wallet file via WalletDocument.Contacts
- Indirizzi: clicking any address (left or right click) opens a modal
  window with derivation path, public key and private key as selectable
  text (no copy button needed — user selects and copies manually);
  AddressRow now carries PubKey, PrivKey, DerivPath pre-computed
- AddressInfoWindow: new Window with SelectableTextBlock per field,
  private key section hidden for watch-only wallets
- Loc: adds tab.contacts, addr.*, contacts.*, send.from.contact keys
  in all 6 languages

src/App/Views/MainWindow.axaml.cs

@@ -1,7 +1,12 @@
 using System.Linq;
+using System.Threading.Tasks;
+using Avalonia;
 using Avalonia.Controls;
+using Avalonia.Input;
+using Avalonia.Input.Platform;
 using Avalonia.Interactivity;
 using Avalonia.Platform.Storage;
+using Avalonia.VisualTree;
 using PalladiumWallet.App.ViewModels;
 
 namespace PalladiumWallet.App.Views;
@@ -13,7 +18,6 @@ public partial class MainWindow : Window
         InitializeComponent();
     }
 
-    /// <summary>File → Apri wallet da file (il picker richiede il TopLevel, da qui).</summary>
     private async void OnOpenWalletFileClick(object? sender, RoutedEventArgs e)
     {
         if (DataContext is not MainWindowViewModel vm)
@@ -32,4 +36,26 @@ public partial class MainWindow : Window
         if (files.FirstOrDefault()?.TryGetLocalPath() is { } path)
             vm.OpenFromPath(path);
     }
+
+    private async void OnAddressListTapped(object? sender, TappedEventArgs e)
+    {
+        if (DataContext is not MainWindowViewModel vm || vm.SelectedAddressRow is not { } row)
+            return;
+        var info = new AddressInfo(vm.Loc, row.Indirizzo, row.DerivPath, row.PubKey, row.PrivKey);
+        await new AddressInfoWindow(info).ShowDialog(this);
+    }
+
+    private async void OnAddressListPointerPressed(object? sender, PointerPressedEventArgs e)
+    {
+        if (!e.GetCurrentPoint(null).Properties.IsRightButtonPressed) return;
+        if (sender is not ListBox lb || DataContext is not MainWindowViewModel vm) return;
+
+        var item = (e.Source as Visual)?.FindAncestorOfType<ListBoxItem>();
+        if (item is not { DataContext: AddressRow row }) return;
+
+        lb.SelectedItem = row;
+
+        var info = new AddressInfo(vm.Loc, row.Indirizzo, row.DerivPath, row.PubKey, row.PrivKey);
+        await new AddressInfoWindow(info).ShowDialog(this);
+    }
 }