Add IDtrBar (#1276)

Dalamud/Plugin/Services/IDtrBar.cs

@@ -0,0 +1,22 @@
+using System;
+
+using Dalamud.Game.Gui.Dtr;
+using Dalamud.Game.Text.SeStringHandling;
+
+namespace Dalamud.Plugin.Services;
+
+/// <summary>
+/// Class used to interface with the server info bar.
+/// </summary>
+public interface IDtrBar
+{
+    /// <summary>
+    /// Get a DTR bar entry.
+    /// This allows you to add your own text, and users to sort it.
+    /// </summary>
+    /// <param name="title">A user-friendly name for sorting.</param>
+    /// <param name="text">The text the entry shows.</param>
+    /// <returns>The entry object used to update, hide and remove the entry.</returns>
+    /// <exception cref="ArgumentException">Thrown when an entry with the specified title exists.</exception>
+    public DtrBarEntry Get(string title, SeString? text = null);
+}