Add standalone OCSentinel setup executable builder

installer/OCSentinelBootstrapper/Program.cs

@@ -0,0 +1,76 @@
+using System.Diagnostics;
+using System.IO.Compression;
+using System.Reflection;
+
+namespace OCSentinelBootstrapper;
+
+internal static class Program
+{
+    private static int Main()
+    {
+        string tempRoot = Path.Combine(Path.GetTempPath(), "OCSentinelSetup", Guid.NewGuid().ToString("N"));
+        string zipPath = Path.Combine(tempRoot, "payload.zip");
+        string extractRoot = Path.Combine(tempRoot, "payload");
+
+        try
+        {
+            Directory.CreateDirectory(tempRoot);
+            Directory.CreateDirectory(extractRoot);
+
+            ExtractEmbeddedPayload(zipPath);
+            ZipFile.ExtractToDirectory(zipPath, extractRoot, overwriteFiles: true);
+
+            string installScript = Path.Combine(extractRoot, "scripts", "install-ocsentinel.ps1");
+            if (!File.Exists(installScript))
+            {
+                throw new FileNotFoundException("Embedded payload did not contain install-ocsentinel.ps1", installScript);
+            }
+
+            var process = new Process
+            {
+                StartInfo = new ProcessStartInfo
+                {
+                    FileName = "powershell.exe",
+                    Arguments = $"-ExecutionPolicy Bypass -File \"{installScript}\"",
+                    UseShellExecute = false
+                }
+            };
+
+            process.Start();
+            process.WaitForExit();
+            return process.ExitCode;
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"OCSentinel installer failed: {ex}");
+            return 1;
+        }
+        finally
+        {
+            try
+            {
+                if (Directory.Exists(tempRoot))
+                {
+                    Directory.Delete(tempRoot, recursive: true);
+                }
+            }
+            catch
+            {
+                // Best-effort cleanup only.
+            }
+        }
+    }
+
+    private static void ExtractEmbeddedPayload(string destinationPath)
+    {
+        Assembly assembly = Assembly.GetExecutingAssembly();
+        using Stream? resourceStream = assembly.GetManifestResourceStream("payload.zip");
+        if (resourceStream is null)
+        {
+            throw new InvalidOperationException("Embedded payload.zip resource was not found.");
+        }
+
+        using FileStream output = File.Create(destinationPath);
+        resourceStream.CopyTo(output);
+    }
+}