add app icon (assets/icon.ico) + generator

Embed via PyInstaller --icon in CI. Regenerate with tools/make_icon.ps1.

.github/workflows/release.yml

@@ -28,7 +28,7 @@ jobs:
         run: echo "version=${GITHUB_REF_NAME#v}" >> "$GITHUB_OUTPUT"
 
       - name: Build executable
-        run: python -m PyInstaller --onefile --uac-admin --console --name dhcpsrv --paths src dhcpsrv-launcher.py
+        run: python -m PyInstaller --onefile --uac-admin --console --name dhcpsrv --icon assets/icon.ico --paths src dhcpsrv-launcher.py
 
       - name: Package portable folder
         shell: pwsh

tools/make_icon.ps1

@@ -0,0 +1,69 @@
+# Regenerate assets/icon.ico for this project.
+# Edit $Text / colors below and re-run.
+
+param(
+    [string]$Text = "DHCP",
+    [int[]]$ColorFrom = @(80, 160, 255),
+    [int[]]$ColorTo   = @(20, 60, 140),
+    [string]$OutPath  = "$PSScriptRoot\..\assets\icon.ico"
+)
+
+Add-Type -AssemblyName System.Drawing
+
+$outDir = Split-Path $OutPath -Parent
+if (-not (Test-Path $outDir)) { New-Item -ItemType Directory -Path $outDir -Force | Out-Null }
+
+$bgFrom = [System.Drawing.Color]::FromArgb(255, $ColorFrom[0], $ColorFrom[1], $ColorFrom[2])
+$bgTo   = [System.Drawing.Color]::FromArgb(255, $ColorTo[0],   $ColorTo[1],   $ColorTo[2])
+
+$sizes = 256, 128, 64, 48, 32, 16
+$pngs = @()
+foreach ($s in $sizes) {
+    $bmp = New-Object System.Drawing.Bitmap $s, $s
+    $g = [System.Drawing.Graphics]::FromImage($bmp)
+    $g.SmoothingMode = 'AntiAlias'
+    $g.TextRenderingHint = 'AntiAliasGridFit'
+
+    $path = New-Object System.Drawing.Drawing2D.GraphicsPath
+    $r = $s - 2
+    $path.AddEllipse(1, 1, $r, $r)
+    $brush = New-Object System.Drawing.Drawing2D.PathGradientBrush($path)
+    $brush.CenterColor = $bgFrom
+    $brush.SurroundColors = @($bgTo)
+    $g.FillEllipse($brush, 1, 1, $r, $r)
+
+    $pen = New-Object System.Drawing.Pen ([System.Drawing.Color]::FromArgb(60, 0, 0, 0)), ([float]($s/64))
+    $g.DrawEllipse($pen, 1, 1, $r, $r)
+
+    $fontSize = [float]($s * 0.32)
+    $font = New-Object System.Drawing.Font "Segoe UI Black", $fontSize, ([System.Drawing.FontStyle]::Bold), ([System.Drawing.GraphicsUnit]::Pixel)
+    $sf = New-Object System.Drawing.StringFormat
+    $sf.Alignment = 'Center'; $sf.LineAlignment = 'Center'
+    $shadow = New-Object System.Drawing.SolidBrush ([System.Drawing.Color]::FromArgb(80, 0, 0, 0))
+    $g.DrawString($Text, $font, $shadow, [float]($s/2 + $s*0.02), [float]($s/2 + $s*0.02), $sf)
+    $g.DrawString($Text, $font, [System.Drawing.Brushes]::White, [float]($s/2), [float]($s/2), $sf)
+    $g.Dispose()
+
+    $ms = New-Object System.IO.MemoryStream
+    $bmp.Save($ms, [System.Drawing.Imaging.ImageFormat]::Png)
+    $pngs += ,@{ size = $s; bytes = $ms.ToArray() }
+    $ms.Dispose(); $bmp.Dispose()
+}
+
+$fs = [System.IO.File]::Create($OutPath)
+$bw = New-Object System.IO.BinaryWriter $fs
+$bw.Write([uint16]0)
+$bw.Write([uint16]1)
+$bw.Write([uint16]$pngs.Count)
+$offset = 6 + 16 * $pngs.Count
+foreach ($p in $pngs) {
+    $w = if ($p.size -ge 256) { 0 } else { $p.size }
+    $bw.Write([byte]$w); $bw.Write([byte]$w)
+    $bw.Write([byte]0); $bw.Write([byte]0)
+    $bw.Write([uint16]1); $bw.Write([uint16]32)
+    $bw.Write([uint32]$p.bytes.Length); $bw.Write([uint32]$offset)
+    $offset += $p.bytes.Length
+}
+foreach ($p in $pngs) { $bw.Write($p.bytes) }
+$bw.Close(); $fs.Close()
+Write-Host "Wrote $OutPath"