Add asynchronous AlternateScreen method

src/Spectre.Console/Extensions/AnsiConsoleExtensions.Screen.cs

@@ -40,5 +40,43 @@ public static void AlternateScreen(this IAnsiConsole console, Action action)
             // Switch back to primary screen
             console.Write(new ControlCode("\u001b[?1049l"));
         }
+    }
+
+    /// <summary>
+    /// Switches to an alternate screen buffer asynchronously if the terminal supports it.
+    /// </summary>
+    /// <param name="console">The console.</param>
+    /// <param name="action">The action to execute within the alternate screen buffer.</param>
+    /// <returns>The result of the function.</returns>
+    public static async Task AlternateScreenAsync(this IAnsiConsole console, Func<Task> action)
+    {
+        if (console is null)
+        {
+            throw new ArgumentNullException(nameof(console));
+        }
+
+        if (!console.Profile.Capabilities.Ansi)
+        {
+            throw new NotSupportedException("Alternate buffers are not supported since your terminal does not support ANSI.");
+        }
+
+        if (!console.Profile.Capabilities.AlternateBuffer)
+        {
+            throw new NotSupportedException("Alternate buffers are not supported by your terminal.");
+        }
+
+        // Switch to alternate screen
+        console.Write(new ControlCode("\u001b[?1049h\u001b[H"));
+
+        try
+        {
+            // Execute custom action
+            await action();
+        }
+        finally
+        {
+            // Switch back to primary screen
+            console.Write(new ControlCode("\u001b[?1049l"));
+        }
     }
 }