Added the guided chat to the BeyondFacts Lab (#1177)

app/MindWork AI Studio/Assistants/BeyondFactsLab/BflThreadLocation.cs

@@ -0,0 +1,14 @@
+namespace AIStudio.Assistants.BeyondFactsLab;
+
+/// <summary>
+/// Where the BeyondFacts Lab keeps a chat: the step of a preparation it belongs to.
+/// </summary>
+/// <param name="ProjectId">The ID of the preparation.</param>
+/// <param name="Step">The step.</param>
+public readonly record struct BflThreadLocation(Guid ProjectId, BflStep Step)
+{
+    /// <summary>
+    /// Gets the ID of the chat, which follows from its place, see BflThreadId.
+    /// </summary>
+    public Guid ChatId => BflThreadId.Of(this.ProjectId, this.Step);
+}