Moved the chats of the BeyondFacts Lab to the embedded chat of assistants (#1203)

app/MindWork AI Studio/Chat/Embedded/EmbeddedChatPreparation.cs

@@ -0,0 +1,38 @@
+namespace AIStudio.Chat.Embedded;
+
+/// <summary>
+/// What an assistant decided while it readied a request of an embedded chat: whether the request goes out, and what it
+/// carries beside the stored chat.
+/// </summary>
+/// <remarks>
+/// Both are decided together, since what a request carries may only be known once it was readied, e.g., which images
+/// of the assistant fit beside the system prompt. A ready preparation which carries more starts from READY:
+/// <c>EmbeddedChatPreparation.READY with { ThreadForRequest = … }</c>.
+/// </remarks>
+public sealed record EmbeddedChatPreparation
+{
+    /// <summary>
+    /// The request goes out with the chat as it is.
+    /// </summary>
+    public static readonly EmbeddedChatPreparation READY = new() { IsReady = true };
+
+    /// <summary>
+    /// The request does not go out; whoever readied it told the user why.
+    /// </summary>
+    public static readonly EmbeddedChatPreparation REFUSED = new() { IsReady = false };
+
+    /// <summary>
+    /// Gets whether the request goes out.
+    /// </summary>
+    public bool IsReady { get; private init; }
+
+    /// <summary>
+    /// Gets the chat which the request sends, e.g., with images which the stored chat never holds. The chat itself by
+    /// default.
+    /// </summary>
+    /// <remarks>
+    /// Called once the message and the block of the answer are in the chat, so that the request carries both. Change a
+    /// copy only: the chat is stored as it is.
+    /// </remarks>
+    public Func<ChatThread, ChatThread> ThreadForRequest { get; init; } = thread => thread;
+}