Add events for PowerShell execution status (running, completed, etc).

src/PowerShellEditorServices.Protocol/LanguageServer/ExecutionStatusChangedEvent.cs

@@ -0,0 +1,17 @@
+using Microsoft.PowerShell.EditorServices.Protocol.MessageProtocol;
+
+namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
+{
+    /// <summary>
+    /// Defines an event type for PowerShell context execution status changes (e.g. execution has completed)
+    /// </summary>
+    public class ExecutionStatusChangedEvent
+    {
+        /// <summary>
+        /// The notification type for execution status change events in the message protocol
+        /// </summary>
+        public static readonly
+            NotificationType<object, object> Type =
+            NotificationType<object, object>.Create("powerShell/executionStatusChanged");
+    }
+}

src/PowerShellEditorServices.Protocol/Server/LanguageServer.cs

@@ -56,7 +56,9 @@ public LanguageServer(
         {
             this.Logger = logger;
             this.editorSession = editorSession;
+            // Attach to the underlying PowerShell context to listen for changes in the runspace or execution status
             this.editorSession.PowerShellContext.RunspaceChanged += PowerShellContext_RunspaceChanged;
+            this.editorSession.PowerShellContext.ExecutionStatusChanged += PowerShellContext_ExecutionStatusChanged;
 
             // Attach to ExtensionService events
             this.editorSession.ExtensionService.CommandAdded += ExtensionService_ExtensionAdded;
@@ -1273,6 +1275,18 @@ await this.messageSender.SendEvent(
                 new Protocol.LanguageServer.RunspaceDetails(e.NewRunspace));
         }
 
+        /// <summary>
+        /// Event hook on the PowerShell context to listen for changes in script execution status
+        /// </summary>
+        /// <param name="sender">the PowerShell context sending the execution event</param>
+        /// <param name="e">details of the execution status change</param>
+        private async void PowerShellContext_ExecutionStatusChanged(object sender, ExecutionStatusChangedEventArgs e)
+        {
+            await this.messageSender.SendEvent(
+                ExecutionStatusChangedEvent.Type,
+                e);
+        }
+
         private async void ExtensionService_ExtensionAdded(object sender, EditorCommand e)
         {
             await this.messageSender.SendEvent(