Added confirmed work states to the BeyondFacts Lab (#1182)

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

@@ -0,0 +1,8 @@
+namespace AIStudio.Assistants.BeyondFactsLab;
+
+/// <summary>
+/// A section of an answer of the model, which starts with a heading such as "## [KEY] Title".
+/// </summary>
+/// <param name="Key">The key between the brackets, as the model wrote it, without spaces around it.</param>
+/// <param name="Text">The text below the heading up to the next one, without empty lines around it.</param>
+public sealed record BflMarkdownSection(string Key, string Text);