Fix progress bar during post-install: step-based advancement with status labels

Replace marquee style (unavailable constant) with manual step-based progress.
SetStatusInit calculates total steps, SetStatus advances bar and updates label
at each major operation so users can see activity instead of a frozen bar.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

PrinterInstaller/PrinterInstaller.iss

@@ -876,13 +876,27 @@ end;
 
 // ─── Progress helpers ────────────────────────────────────────────────────────
 
-// Switch the wizard progress bar to marquee (animated) mode and update the
+// Update the status label and advance the progress bar during post-install.
-// status label so the user knows what is happening during the post-install phase.
+// Call SetStatusInit first to reset the bar, then SetStatus for each step.
+var
+  GaugeStep, GaugeTotal: Integer;
+
+procedure SetStatusInit(Total: Integer);
+begin
+  GaugeTotal := Total;
+  GaugeStep  := 0;
+  WizardForm.ProgressGauge.Min      := 0;
+  WizardForm.ProgressGauge.Max      := Total;
+  WizardForm.ProgressGauge.Position := 0;
+end;
+
 procedure SetStatus(const Msg: String);
 begin
-  WizardForm.ProgressGauge.Style   := pbstMarquee;
+  if GaugeStep < GaugeTotal then
-  WizardForm.StatusLabel.Caption   := Msg;
+    GaugeStep := GaugeStep + 1;
-  WizardForm.FileNameLabel.Caption := '';
+  WizardForm.ProgressGauge.Position := GaugeStep;
+  WizardForm.StatusLabel.Caption    := Msg;
+  WizardForm.FileNameLabel.Caption  := '';
   Application.ProcessMessages;
 end;
 
@@ -923,6 +937,16 @@ begin
     ForceDirectories(LogDir);
     LogPath := LogDir + '\printer_install.log';
 
+    // Initialise progress bar: fixed steps + one per printer being changed
+    begin
+      var StepCount: Integer;
+      StepCount := 4; // cleanup + staging + 2x spooler restart
+      for I := 0 to GetArrayLength(PrinterDataArray) - 1 do
+        if PrinterSelectionPage.Values[I] <> PrinterDataArray[I].IsInstalled then
+          StepCount := StepCount + 1;
+      SetStatusInit(StepCount);
+    end;
+
     // ── Step 0: Remove legacy printers from old print servers ────────────────
     SetStatus('Removing legacy printers...');
     CleanedCount := CleanupLegacyPrinters();
@@ -1192,10 +1216,10 @@ begin
         SetDefaultPrinterAllUsers(DefaultPrinter);
     end;
 
-    // Restore progress bar to normal completed state
+    // Fill bar to completion
-    WizardForm.ProgressGauge.Style    := pbstNormal;
     WizardForm.ProgressGauge.Position := WizardForm.ProgressGauge.Max;
     WizardForm.StatusLabel.Caption    := 'Installation complete.';
+    WizardForm.FileNameLabel.Caption  := '';
     Application.ProcessMessages;
 
     // Save log