Added the BeyondFacts Lab as a prototype (#1175)

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

@@ -0,0 +1,57 @@
+namespace AIStudio.Assistants.BeyondFactsLab;
+
+/// <summary>
+/// A preparation in the BeyondFacts Lab: one event, for which a person works through the steps of the lab.
+/// </summary>
+/// <remarks>
+/// The lab stores it as project.json in the folder of the preparation. Everything else the preparation
+/// holds lies in files beside it, which the lab finds by the ID of the preparation, never by a stored path.
+/// </remarks>
+public sealed class BflProject
+{
+    /// <summary>
+    /// The version of the stored form this version of AI Studio writes.
+    /// </summary>
+    /// <remarks>
+    /// A preparation of a newer form is listed but neither opened nor written, so that an older version of
+    /// AI Studio cannot lose what a newer one stored. Raise it with every field a released version does not
+    /// know yet: that version refuses fields it does not know, and only the higher number tells the person
+    /// that a newer version stored the preparation.
+    /// </remarks>
+    public const int CURRENT_SCHEMA_VERSION = 1;
+
+    /// <summary>
+    /// Gets or sets the version of the stored form.
+    /// </summary>
+    public int SchemaVersion { get; set; } = CURRENT_SCHEMA_VERSION;
+
+    /// <summary>
+    /// Gets or sets the ID of the preparation, which is also the name of its folder.
+    /// </summary>
+    public Guid ProjectId { get; set; }
+
+    /// <summary>
+    /// Gets or sets the name the person gave the preparation.
+    /// </summary>
+    public string Name { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Gets or sets when the preparation was created.
+    /// </summary>
+    public DateTimeOffset CreatedAtUtc { get; set; }
+
+    /// <summary>
+    /// Gets or sets when the preparation was changed last.
+    /// </summary>
+    public DateTimeOffset ModifiedAtUtc { get; set; }
+
+    /// <summary>
+    /// Gets or sets when the person marked the event as having taken place, or null while it has not.
+    /// </summary>
+    public DateTimeOffset? HappenedAtUtc { get; set; }
+
+    /// <summary>
+    /// Gets or sets the step the person looked at last, where the lab opens the preparation again.
+    /// </summary>
+    public BflStep CurrentStep { get; set; } = BflStep.FRAMEWORK;
+}