ci: add MSIX packaging script

scripts/msix/build_msix.ps1

@@ -0,0 +1,67 @@
+<#
+Builds the unsigned MSIX Store package from an existing install tree.
+The package is intentionally NOT signed: the Microsoft Store strips and
+re-signs uploads with Microsoft's certificate. For local installs use
+Developer Mode loose-layout registration instead:
+  ./scripts/msix/build_msix.ps1 -StageOnly
+  Add-AppxPackage -Register <staging>\AppxManifest.xml
+Requires the Windows SDK (makeappx.exe) unless -StageOnly is used.
+#>
+param(
+    [string]$InstallDir = "build/OrcaSlicer",
+    [string]$OutputPath = "build/OrcaSlicer_Windows_MSIX.msix",
+    [string]$StagingDir = "",
+    [switch]$StageOnly,
+    [string]$IdentityName = "OrcaSlicer.Dev",
+    [string]$Publisher = "CN=00000000-0000-0000-0000-000000000000",
+    [string]$PublisherDisplayName = "OrcaSlicer (dev)"
+)
+$ErrorActionPreference = 'Stop'
+
+$repoRoot = Split-Path (Split-Path $PSScriptRoot -Parent) -Parent
+
+# MSIX version = MAJOR.MINOR.PATCH.0 from the SoftFever_VERSION semver triplet
+# (Store requires the revision field to be 0).
+$versionContent = Get-Content (Join-Path $repoRoot 'version.inc') -Raw
+if ($versionContent -notmatch 'set\(SoftFever_VERSION "(\d+)\.(\d+)\.(\d+)') {
+    throw "Could not parse SoftFever_VERSION from version.inc"
+}
+$msixVersion = "$($Matches[1]).$($Matches[2]).$($Matches[3]).0"
+Write-Output "MSIX version: $msixVersion"
+
+if (-not (Test-Path (Join-Path $InstallDir 'orca-slicer.exe'))) {
+    throw "orca-slicer.exe not found in '$InstallDir' - build the install tree first"
+}
+
+if ([string]::IsNullOrEmpty($StagingDir)) {
+    $StagingDir = Join-Path ([System.IO.Path]::GetTempPath()) 'orca-msix-staging'
+}
+if (Test-Path $StagingDir) { Remove-Item $StagingDir -Recurse -Force }
+New-Item -ItemType Directory -Force $StagingDir | Out-Null
+
+Copy-Item -Path (Join-Path $InstallDir '*') -Destination $StagingDir -Recurse
+Copy-Item -Path (Join-Path $PSScriptRoot 'assets') -Destination (Join-Path $StagingDir 'Assets') -Recurse
+
+$manifest = Get-Content (Join-Path $PSScriptRoot 'AppxManifest.xml') -Raw
+$manifest = $manifest.Replace('@MSIX_VERSION@', $msixVersion)
+$manifest = $manifest.Replace('@MSIX_IDENTITY_NAME@', $IdentityName)
+$manifest = $manifest.Replace('@MSIX_PUBLISHER@', $Publisher)
+$manifest = $manifest.Replace('@MSIX_PUBLISHER_DISPLAY_NAME@', $PublisherDisplayName)
+Set-Content -Path (Join-Path $StagingDir 'AppxManifest.xml') -Value $manifest -Encoding utf8
+
+if ($StageOnly) {
+    Write-Output "Staged loose layout at: $StagingDir"
+    exit 0
+}
+
+$makeappx = Get-ChildItem "${env:ProgramFiles(x86)}\Windows Kits\10\bin\10.*\x64\makeappx.exe" -ErrorAction SilentlyContinue |
+    Sort-Object { [version]$_.Directory.Parent.Name } -Descending |
+    Select-Object -First 1 -ExpandProperty FullName
+if (-not $makeappx) {
+    throw "makeappx.exe not found under '${env:ProgramFiles(x86)}\Windows Kits\10\bin' - install the Windows SDK"
+}
+Write-Output "Using makeappx: $makeappx"
+
+& $makeappx pack /d $StagingDir /p $OutputPath /o
+if ($LASTEXITCODE -ne 0) { throw "makeappx pack failed with exit code $LASTEXITCODE" }
+Write-Output "Packed: $OutputPath"