feat: Initialize Zastava Webhook service with TLS and Authority authentication

- Added Program.cs to set up the web application with Serilog for logging, health check endpoints, and a placeholder admission endpoint.
- Configured Kestrel server to use TLS 1.3 and handle client certificates appropriately.
- Created StellaOps.Zastava.Webhook.csproj with necessary dependencies including Serilog and Polly.
- Documented tasks in TASKS.md for the Zastava Webhook project, outlining current work and exit criteria for each task.

Mongo2Go-4.1.0/src/Mongo2Go/Helper/PortPool.cs

@@ -0,0 +1,37 @@
+using System;
+
+namespace Mongo2Go.Helper
+{
+    /// <summary>
+    /// Intention: port numbers won't be assigned twice to avoid connection problems with integration tests
+    /// </summary>
+    public sealed class PortPool : IPortPool
+    {
+        private static readonly PortPool Instance = new PortPool();
+
+        // Explicit static constructor to tell C# compiler
+        // not to mark type as beforefieldinit
+        static PortPool()
+        {
+        }
+
+        // Singleton
+        private PortPool()
+        {
+        }
+
+        public static PortPool GetInstance
+        {
+            get { return Instance; }
+        }
+
+        /// <summary>
+        /// Returns and reserves a new port
+        /// </summary>
+        public int GetNextOpenPort()
+        {
+            IPortWatcher portWatcher = PortWatcherFactory.CreatePortWatcher();
+            return portWatcher.FindOpenPort();
+        }
+    }
+}