v0.16.0 — ThemedMessageBox replacing native MessageBox everywhere

The Win32 MessageBox uses the system white-on-gray look that clashes
with the launcher's dark theme (jarring transition every time we
confirm a cancel, show an error, etc.). Replaced with a custom WPF
dialog that:

- Drops in : same Show(message, title, button, icon, default) API as
  System.Windows.MessageBox, returns the same MessageBoxResult.
- Looks native to the launcher : dark Brush.Bg.Window background,
  Brush.Border outline, Brush.Text.Primary content, AccentButton for
  the default action and SecondaryButton for the others.
- Iconography by emoji + colour code : ⛔ red (Error), ⚠ amber (Warning),
  ❓ neutral (Question), ℹ blue (Information). Mapped from MessageBoxImage.
- Buttons localised via Strings.ActionOk / ActionYes / ActionNo /
  ActionCancel — works in fr/en/zh/th/ar like the rest of the UI.
- Owner = currently active window (falls back to MainWindow then
  CenterScreen) so it positions correctly even from a child dialog.
- Esc resolves to Cancel/No matching MessageBox semantics.

The 21 MessageBox.Show call sites across MainViewModel, SettingsViewModel,
LicenseDetailsDialog and MainWindow now use ThemedMessageBox.Show with
no signature change — full grep replace + tiny `using` adjustments.

Versions bumped to 0.16.0.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/PSLauncher.App/ViewModels/MainViewModel.cs

@@ -438,7 +438,7 @@ public sealed partial class MainViewModel : ObservableObject
         catch (Exception ex)
         {
             _logger.LogError(ex, "Self-update failed");
-            MessageBox.Show(Strings.MsgSelfUpdateFailed(ex.Message),
+            ThemedMessageBox.Show(Strings.MsgSelfUpdateFailed(ex.Message),
                 Strings.MsgBoxError, MessageBoxButton.OK, MessageBoxImage.Error);
             StatusMessage = Strings.StatusSelfUpdateError(ex.Message);
             IsBusy = false;
@@ -518,7 +518,7 @@ public sealed partial class MainViewModel : ObservableObject
     private void CancelDownload()
     {
         if (_activeDownloadCts is null || _activeRow is null) return;
-        var confirm = MessageBox.Show(
+        var confirm = ThemedMessageBox.Show(
             Strings.MsgCancelDownloadConfirm(_activeRow.Version),
             Strings.MsgBoxCancelDl,
             MessageBoxButton.YesNo, MessageBoxImage.Question, MessageBoxResult.No);
@@ -535,7 +535,7 @@ public sealed partial class MainViewModel : ObservableObject
         // Si un DL est actif sur cette même row, on doit d'abord l'annuler proprement.
         var st = _downloadManager.GetResumableState(row.Version);
         var sizeStr = FormatSize(st?.DownloadedBytes ?? 0);
-        var confirm = MessageBox.Show(
+        var confirm = ThemedMessageBox.Show(
             Strings.MsgRestartDownloadConfirm(row.Version, sizeStr),
             Strings.MsgBoxRestartDl,
             MessageBoxButton.YesNo, MessageBoxImage.Warning, MessageBoxResult.No);
@@ -605,7 +605,7 @@ public sealed partial class MainViewModel : ObservableObject
         catch (Exception ex)
         {
             _logger.LogError(ex, "Launch failed");
-            MessageBox.Show(Strings.MsgLaunchFailed(ex.Message),
+            ThemedMessageBox.Show(Strings.MsgLaunchFailed(ex.Message),
                 Strings.MsgBoxLaunchError, MessageBoxButton.OK, MessageBoxImage.Error);
         }
     }
@@ -613,7 +613,7 @@ public sealed partial class MainViewModel : ObservableObject
     private async Task InstallVersionAsync(VersionRowViewModel row)
     {
         if (row.Remote is null) return;
-        if (IsBusy) { MessageBox.Show(Strings.MsgBusy, Strings.MsgBoxPatience, MessageBoxButton.OK, MessageBoxImage.Information); return; }
+        if (IsBusy) { ThemedMessageBox.Show(Strings.MsgBusy, Strings.MsgBoxPatience, MessageBoxButton.OK, MessageBoxImage.Information); return; }
 
         IsBusy = true;
         _activeRow = row;
@@ -738,7 +738,7 @@ public sealed partial class MainViewModel : ObservableObject
                     // notifie l'utilisateur que la DB n'a pas été migrée — la prochaine relance
                     // de l'install (ou un Settings → "Rejouer migrations") tentera à nouveau.
                     _logger.LogError("DB migration failed for v{Version}: {Detail}", row.Version, migResult.FailureMessage);
-                    MessageBox.Show(
+                    ThemedMessageBox.Show(
                         Strings.MsgMigrationFailed(migResult.FailureMessage ?? "?"),
                         Strings.MsgBoxMigrationFailed,
                         MessageBoxButton.OK, MessageBoxImage.Warning);
@@ -779,13 +779,13 @@ public sealed partial class MainViewModel : ObservableObject
                         _logger.LogInformation("No _report/ in v{Version} ZIP, report tool unchanged", row.Version);
                         break;
                     case DeployStatus.XamppNotFound:
-                        MessageBox.Show(
+                        ThemedMessageBox.Show(
                             Strings.MsgReportXamppNotFound(_config.ReportTool.HtdocsRoot),
                             Strings.MsgBoxReportDeployFailed,
                             MessageBoxButton.OK, MessageBoxImage.Warning);
                         break;
                     case DeployStatus.Failed:
-                        MessageBox.Show(
+                        ThemedMessageBox.Show(
                             Strings.MsgReportDeployFailed(rdResult.ErrorMessage ?? "?"),
                             Strings.MsgBoxReportDeployFailed,
                             MessageBoxButton.OK, MessageBoxImage.Warning);
@@ -818,7 +818,7 @@ public sealed partial class MainViewModel : ObservableObject
             row.State = VersionRowState.AvailableIdle;
             row.ProgressDetail = null;
             row.ProgressPercent = 0;
-            MessageBox.Show(
+            ThemedMessageBox.Show(
                 Strings.MsgInstallFailed(ex.Message),
                 Strings.MsgBoxError, MessageBoxButton.OK, MessageBoxImage.Error);
             StatusMessage = Strings.StatusError(ex.Message);
@@ -841,14 +841,14 @@ public sealed partial class MainViewModel : ObservableObject
         if (row.Installed is null) return;
 
         var sizeStr = FormatSize(row.SizeBytes);
-        var confirm = MessageBox.Show(
+        var confirm = ThemedMessageBox.Show(
             Strings.MsgUninstallConfirm(row.Version, row.FolderPath, sizeStr),
             Strings.MsgBoxConfirm,
             MessageBoxButton.YesNo, MessageBoxImage.Warning, MessageBoxResult.No);
 
         if (confirm != MessageBoxResult.Yes) return;
 
-        if (IsBusy) { MessageBox.Show(Strings.MsgBusy, Strings.MsgBoxPatience, MessageBoxButton.OK, MessageBoxImage.Information); return; }
+        if (IsBusy) { ThemedMessageBox.Show(Strings.MsgBusy, Strings.MsgBoxPatience, MessageBoxButton.OK, MessageBoxImage.Information); return; }
 
         IsBusy = true;
         row.State = VersionRowState.Uninstalling;
@@ -863,7 +863,7 @@ public sealed partial class MainViewModel : ObservableObject
         {
             _logger.LogError(ex, "Uninstall failed for {Version}", row.Version);
             row.State = VersionRowState.InstalledIdle;
-            MessageBox.Show(Strings.MsgUninstallFailed(ex.Message), Strings.MsgBoxError,
+            ThemedMessageBox.Show(Strings.MsgUninstallFailed(ex.Message), Strings.MsgBoxError,
                 MessageBoxButton.OK, MessageBoxImage.Error);
             StatusMessage = Strings.StatusError(ex.Message);
         }
@@ -878,7 +878,7 @@ public sealed partial class MainViewModel : ObservableObject
         var url = row.Remote?.ReleaseNotesUrl;
         if (string.IsNullOrEmpty(url))
         {
-            MessageBox.Show(Strings.MsgNoReleaseNotes,
+            ThemedMessageBox.Show(Strings.MsgNoReleaseNotes,
                 Strings.MsgBoxReleaseNotes, MessageBoxButton.OK, MessageBoxImage.Information);
             return;
         }
@@ -887,7 +887,7 @@ public sealed partial class MainViewModel : ObservableObject
         catch (Exception ex)
         {
             _logger.LogWarning(ex, "Failed to fetch release notes");
-            MessageBox.Show(Strings.MsgReleaseNotesFetchFailed(ex.Message),
+            ThemedMessageBox.Show(Strings.MsgReleaseNotesFetchFailed(ex.Message),
                 Strings.MsgBoxError, MessageBoxButton.OK, MessageBoxImage.Warning);
             return;
         }