deprecate(lmxproxy): move all LmxProxy code, tests, and docs to deprecated/

LmxProxy is no longer needed. Moved the entire lmxproxy/ workspace, DCL
adapter files, and related docs to deprecated/. Removed LmxProxy registration
from DataConnectionFactory, project reference from DCL, protocol option from
UI, and cleaned up all requirement docs.

deprecated/lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Host/Domain/ConnectionState.cs

@@ -0,0 +1,38 @@
+namespace ZB.MOM.WW.LmxProxy.Host.Domain
+{
+    /// <summary>
+    ///     Represents the state of a SCADA client connection.
+    /// </summary>
+    public enum ConnectionState
+    {
+        /// <summary>
+        ///     The client is disconnected.
+        /// </summary>
+        Disconnected,
+
+        /// <summary>
+        ///     The client is in the process of connecting.
+        /// </summary>
+        Connecting,
+
+        /// <summary>
+        ///     The client is connected.
+        /// </summary>
+        Connected,
+
+        /// <summary>
+        ///     The client is in the process of disconnecting.
+        /// </summary>
+        Disconnecting,
+
+        /// <summary>
+        ///     The client encountered an error.
+        /// </summary>
+        Error,
+
+        /// <summary>
+        ///     The client is reconnecting after a connection loss.
+        /// </summary>
+        Reconnecting
+    }
+}