Polish GUI and add app icon

scripts/Build-MrTrustExe.ps1

@@ -13,6 +13,7 @@ function Resolve-FullPath {
 
 $root = Split-Path -Parent (Split-Path -Parent $MyInvocation.MyCommand.Path)
 $sourcePath = Join-Path $root "src\MrTrustLauncher.cs"
+$iconPath = Join-Path $root "assets\MrTrust.ico"
 $resolvedOutputPath = Resolve-FullPath $OutputPath
 $outputDirectory = Split-Path -Parent $resolvedOutputPath
 
@@ -20,6 +21,10 @@ if (-not (Test-Path -LiteralPath $sourcePath)) {
     throw "Launcher source not found: $sourcePath"
 }
 
+if (-not (Test-Path -LiteralPath $iconPath)) {
+    & (Join-Path $root "scripts\New-MrTrustIcon.ps1") -OutputPath $iconPath
+}
+
 New-Item -ItemType Directory -Force -Path $outputDirectory | Out-Null
 
 $compilerCandidates = @(
@@ -38,6 +43,7 @@ if (-not $compiler) {
     /optimize+ `
     /platform:anycpu `
     /out:$resolvedOutputPath `
+    /win32icon:$iconPath `
     /reference:System.Windows.Forms.dll `
     /reference:System.Drawing.dll `
     $sourcePath