feat: add indeterminate progress bar and button state during simulation (#64)

- ProgressBar IsIndeterminate visible while IsRunning
- Button text changes to 'Running...' during simulation
- Button disabled during execution, re-enabled after

Author: JusterZhu

src/ViewModels/SimulateViewModel.cs

@@ -20,6 +20,7 @@ public partial class SimulateViewModel : ViewModelBase
 
     [ObservableProperty] private bool _isRunning;
     [ObservableProperty] private string _status;
+    [ObservableProperty] private string _startButtonText;
     [ObservableProperty] private ObservableCollection<string> _log = new();
 
     public ObservableCollection<PlatformItem> Platforms { get; } = new()
@@ -37,6 +38,7 @@ public partial class SimulateViewModel : ViewModelBase
     public SimulateViewModel()
     {
         _status = _loc["Patch.Ready"];
+        _startButtonText = _loc["Sim.Start"];
     }
 
     /// <summary>
@@ -90,7 +92,7 @@ async Task StartSimulation()
         if (string.IsNullOrWhiteSpace(Config.PatchFilePath)) { Status = _loc["Sim.ValidateDirs"]; return; }
         if (string.IsNullOrWhiteSpace(Config.OutputDirectory)) { Status = _loc["Sim.ValidateDirs"]; return; }
 
-        IsRunning = true; Log.Clear(); Status = _loc["Sim.Starting"];
+        IsRunning = true; StartButtonText = "⏳ Running..."; Log.Clear(); Status = _loc["Sim.Starting"];
         try
         {
             var progress = new Progress<string>(L);
@@ -116,7 +118,7 @@ async Task StartSimulation()
             var reportPath = await _report.GenerateAsync(Config, failResult, Config.OutputDirectory);
             L(_loc.T("Sim.Report", reportPath));
         }
-        finally { IsRunning = false; }
+        finally { IsRunning = false; StartButtonText = _loc["Sim.Start"]; }
     }
 
     void L(string msg) => Log.Add($"[{DateTime.Now:HH:mm:ss}] {msg}");

src/Views/SimulateView.axaml

@@ -82,9 +82,10 @@
             </Border>
 
             <!-- Run -->
-            <Button Content="{Binding Source={x:Static svc:LocalizationService.Instance}, Path=[Sim.Start]}"
+            <Button Content="{Binding StartButtonText}"
                     Command="{Binding StartSimulationCommand}"
                     IsEnabled="{Binding !IsRunning}" Height="40" FontSize="14" HorizontalAlignment="Stretch"/>
+            <ProgressBar IsVisible="{Binding IsRunning}" IsIndeterminate="True" Height="4"/>
             <TextBlock Text="{Binding Status}" FontSize="13"/>
 
             <!-- Log -->