Add standalone OCSentinel setup executable builder

build/build-client-installer.ps1

@@ -0,0 +1,50 @@
+param(
+    [string]$Configuration = "Release"
+)
+
+$ErrorActionPreference = "Stop"
+
+$repoRoot = Split-Path -Parent $PSScriptRoot
+$artifactsRoot = Join-Path $repoRoot "artifacts"
+$zipPath = Join-Path $artifactsRoot "OCSentinelClient-win-x64.zip"
+$bootstrapperRoot = Join-Path $repoRoot "installer\OCSentinelBootstrapper"
+$payloadPath = Join-Path $bootstrapperRoot "payload.zip"
+$projectPath = Join-Path $bootstrapperRoot "OCSentinelBootstrapper.csproj"
+$publishRoot = Join-Path $artifactsRoot "bootstrapper-publish\win-x64"
+$outputExe = Join-Path $artifactsRoot "OCSentinelSetup.exe"
+
+if (-not (Test-Path $zipPath)) {
+    & powershell.exe -ExecutionPolicy Bypass -File (Join-Path $repoRoot "build\build-client-package.ps1") -Configuration $Configuration
+    if ($LASTEXITCODE -ne 0) {
+        throw "build-client-package.ps1 failed"
+    }
+}
+
+Copy-Item -Path $zipPath -Destination $payloadPath -Force
+
+if (Test-Path $publishRoot) {
+    Remove-Item -LiteralPath $publishRoot -Recurse -Force
+}
+
+if (Test-Path $outputExe) {
+    Remove-Item -LiteralPath $outputExe -Force
+}
+
+New-Item -ItemType Directory -Force -Path $publishRoot | Out-Null
+
+& dotnet publish $projectPath `
+    -c $Configuration `
+    -r win-x64 `
+    --self-contained true `
+    -p:PublishSingleFile=true `
+    -p:EnableCompressionInSingleFile=true `
+    -p:IncludeNativeLibrariesForSelfExtract=true `
+    -o $publishRoot
+
+if ($LASTEXITCODE -ne 0) {
+    throw "dotnet publish failed for bootstrapper"
+}
+
+Copy-Item -Path (Join-Path $publishRoot "OCSentinelBootstrapper.exe") -Destination $outputExe -Force
+
+Write-Host "OfficeCom Sentinel setup executable created at $outputExe"