Add shared runner dependency setup for Linux and Windows

scripts/ci/install-windows.ps1

@@ -0,0 +1,70 @@
+# Installs job-local PowerShell and Rust dependencies for the Windows launcher.
+param([ValidateSet('Launcher')][string]$Mode = 'Launcher')
+$ErrorActionPreference = 'Stop'
+if (-not [Environment]::OSVersion.Platform.ToString().StartsWith('Win')) {
+    throw 'This setup tool requires Windows.'
+}
+[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
+if (-not $env:RUNNER_TEMP) { $env:RUNNER_TEMP = $env:TEMP }
+
+function Add-RunnerPath([string]$Directory) {
+    $env:PATH = "$Directory;$env:PATH"
+    foreach ($pathFile in @($env:GITHUB_PATH, $env:GITEA_PATH)) {
+        if ($pathFile) { Add-Content -Path $pathFile -Value $Directory }
+    }
+}
+
+$pwsh = Get-Command pwsh.exe -ErrorAction SilentlyContinue | Select-Object -First 1 -ExpandProperty Source
+if (-not $pwsh) {
+    $machinePwsh = Join-Path $env:ProgramFiles 'PowerShell\7\pwsh.exe'
+    if (Test-Path $machinePwsh) { $pwsh = $machinePwsh }
+}
+if (-not $pwsh) {
+    $version = '7.6.6'
+    $installDir = Join-Path $env:RUNNER_TEMP "scopenet-pwsh-$version"
+    $pwsh = Join-Path $installDir 'pwsh.exe'
+    if (-not (Test-Path $pwsh)) {
+        New-Item -ItemType Directory -Force -Path $installDir | Out-Null
+        $archive = Join-Path $env:RUNNER_TEMP "PowerShell-$version-win-x64.zip"
+        Invoke-WebRequest -UseBasicParsing -Uri "https://github.com/PowerShell/PowerShell/releases/download/v$version/PowerShell-$version-win-x64.zip" -OutFile $archive
+        Expand-Archive -Path $archive -DestinationPath $installDir -Force
+        Remove-Item $archive
+    }
+}
+Add-RunnerPath (Split-Path $pwsh)
+Write-Host "PowerShell $(& $pwsh -NoProfile -Command '$PSVersionTable.PSVersion.ToString()') is ready."
+
+$cargoBin = Join-Path $env:USERPROFILE '.cargo\bin'
+Add-RunnerPath $cargoBin
+if (-not (Get-Command rustup.exe -ErrorAction SilentlyContinue)) {
+    $installer = Join-Path $env:RUNNER_TEMP 'scopenet-rustup-init.exe'
+    Invoke-WebRequest -UseBasicParsing -Uri 'https://static.rust-lang.org/rustup/dist/x86_64-pc-windows-msvc/rustup-init.exe' -OutFile $installer
+    & $installer -y --profile minimal --default-toolchain stable
+    if ($LASTEXITCODE -ne 0) { throw "rustup installer failed with exit code $LASTEXITCODE" }
+    Remove-Item $installer
+}
+& rustup toolchain install stable-x86_64-pc-windows-msvc --profile minimal --component clippy --component rustfmt
+if ($LASTEXITCODE -ne 0) { throw "Rust toolchain install failed with exit code $LASTEXITCODE" }
+& rustup default stable-x86_64-pc-windows-msvc
+if ($LASTEXITCODE -ne 0) { throw "Rust toolchain selection failed with exit code $LASTEXITCODE" }
+
+$vswhere = Join-Path ${env:ProgramFiles(x86)} 'Microsoft Visual Studio\Installer\vswhere.exe'
+$vsPath = if (Test-Path $vswhere) { & $vswhere -latest -products * -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property installationPath }
+if (-not $vsPath) {
+    $installer = Join-Path $env:RUNNER_TEMP 'scopenet-vs-buildtools.exe'
+    Invoke-WebRequest -UseBasicParsing -Uri 'https://aka.ms/vs/17/release/vs_buildtools.exe' -OutFile $installer
+    $arguments = @('--quiet', '--wait', '--norestart', '--add', 'Microsoft.VisualStudio.Workload.VCTools', '--includeRecommended')
+    $process = Start-Process -FilePath $installer -ArgumentList $arguments -Wait -PassThru
+    if ($process.ExitCode -eq 3010) { throw 'Microsoft C++ Build Tools installed, but Windows must be restarted before this runner can build.' }
+    if ($process.ExitCode -ne 0) { throw "Microsoft C++ Build Tools installation failed with exit code $($process.ExitCode). Run the runner with administrator rights." }
+    Remove-Item $installer
+    $vsPath = if (Test-Path $vswhere) { & $vswhere -latest -products * -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property installationPath }
+    if (-not $vsPath) { throw 'Microsoft C++ Build Tools installation did not provide the x64 MSVC compiler.' }
+}
+Write-Host "Microsoft C++ Build Tools are ready at $vsPath."
+foreach ($tool in @('cargo.exe', 'rustc.exe', 'node.exe', 'npm.cmd')) {
+    if (-not (Get-Command $tool -ErrorAction SilentlyContinue)) { throw "Missing $tool after dependency setup." }
+}
+$nodeMajor = [int](& node -p 'process.versions.node.split(".")[0]')
+if ($nodeMajor -lt 22) { throw 'Node 22+ is required.' }
+Write-Host "Windows $Mode dependencies are ready."