docs: add xml comments for Essentials routing

src/PepperDash.Essentials.Core/Routing/RoutingPort.cs

@@ -4,18 +4,47 @@
 namespace PepperDash.Essentials.Core
 {
     /// <summary>
-    /// Base class for RoutingInput and Output ports
+    /// Base class for <see cref="RoutingInputPort"/> and <see cref="RoutingOutputPort"/>.
     /// </summary>
     public abstract class RoutingPort : IKeyed
 	{
+		/// <summary>
+		/// The unique key identifying this port within its parent device.
+		/// </summary>
 		public string Key { get; private set; }
+		/// <summary>
+		/// The type of signal this port handles (e.g., Audio, Video, AudioVideo).
+		/// </summary>
 		public eRoutingSignalType Type { get; private set; }
+		/// <summary>
+		/// The physical connection type of this port (e.g., Hdmi, Rca, Dm).
+		/// </summary>
 		public eRoutingPortConnectionType ConnectionType { get; private set; }
+		/// <summary>
+		/// An object (often a number or string) used by the parent routing device to select this port during switching.
+		/// </summary>
 		public readonly object Selector;
+		/// <summary>
+		/// Indicates if this port represents an internal connection within a device (e.g., card to backplane).
+		/// </summary>
 		public bool IsInternal { get; private set; }
+        /// <summary>
+        /// An object used to match feedback values to this port, if applicable.
+        /// </summary>
         public object FeedbackMatchObject { get; set; }
+        /// <summary>
+        /// A reference to the underlying hardware port object (e.g., SimplSharpPro Port), if applicable.
+        /// </summary>
         public object Port { get; set; }
 
+		/// <summary>
+		/// Initializes a new instance of the <see cref="RoutingPort"/> class.
+		/// </summary>
+		/// <param name="key">The unique key for this port.</param>
+		/// <param name="type">The signal type supported by this port.</param>
+		/// <param name="connType">The physical connection type of this port.</param>
+		/// <param name="selector">The selector object for switching.</param>
+		/// <param name="isInternal">True if this port is internal.</param>
 		public RoutingPort(string key, eRoutingSignalType type, eRoutingPortConnectionType connType, object selector, bool isInternal)
 		{
 			Key = key;