add desktop build support

scripts/build-desktop.ps1

@@ -0,0 +1,48 @@
+param(
+    [switch]$OneFile
+)
+
+Set-StrictMode -Version Latest
+$ErrorActionPreference = "Stop"
+
+$repoRoot = Split-Path -Parent $PSScriptRoot
+Set-Location $repoRoot
+
+$pythonExe = if (Test-Path ".\.venv\Scripts\python.exe") {
+    ".\.venv\Scripts\python.exe"
+} else {
+    "python"
+}
+$frontendDist = Join-Path $repoRoot "frontend\dist"
+
+Write-Host "Building frontend bundle..."
+npm run build
+
+Write-Host "Installing desktop build dependencies..."
+& $pythonExe -m pip install -e ".[desktop]"
+
+$mode = if ($OneFile) { "--onefile" } else { "--onedir" }
+
+$pyInstallerArgs = @(
+    "-m", "PyInstaller",
+    "desktop.py",
+    "--noconfirm",
+    "--clean",
+    "--name", "Argonode",
+    "--windowed",
+    $mode,
+    "--distpath", "desktop-dist",
+    "--workpath", "desktop-build",
+    "--specpath", "desktop-build",
+    "--add-data", "${frontendDist};frontend/dist",
+    "--collect-all", "matplotlib",
+    "--collect-all", "scipy",
+    "--collect-all", "skimage",
+    "--collect-all", "webview"
+)
+
+Write-Host "Packaging desktop app..."
+& $pythonExe @pyInstallerArgs
+
+Write-Host "Desktop build complete."
+Write-Host "Output folder: $repoRoot\desktop-dist\Argonode"