Added formulas from LaTeX code blocks and buttons to copy and save formulas (#1154)

app/MindWork AI Studio/Chat/MathJaxBlock.razor.cs

@@ -2,17 +2,41 @@ using Microsoft.AspNetCore.Components;
 
 namespace AIStudio.Chat;
 
+/// <summary>
+/// A formula of its own in the chat, which MathJax typesets, with a button to copy it and the actions
+/// of its file, such as a button to save it.
+/// </summary>
+/// <remarks>
+/// The buttons stand next to the element MathJax typesets, not inside it: MathJax replaces the content
+/// of that element, see chat-math.js.
+/// </remarks>
 public partial class MathJaxBlock
 {
+    /// <summary>
+    /// The formula, without the markers around it. The copy button copies it like this.
+    /// </summary>
     [Parameter]
     public string Value { get; init; } = string.Empty;
 
     [Parameter]
     public string Class { get; init; } = string.Empty;
 
+    /// <summary>
+    /// The file of the formula, as PlainFileExport.ExtractFiles read it, or null when the formula
+    /// cannot be saved, for example in a message whose code blocks cannot be saved either.
+    /// </summary>
+    [Parameter]
+    public MessageFile? File { get; init; }
+
+    /// <summary>
+    /// What to show next to the copy button for the file, for example a button to save it.
+    /// </summary>
+    [Parameter]
+    public RenderFragment<MessageFile>? Actions { get; init; }
+
     private string RootClass => string.IsNullOrWhiteSpace(this.Class)
-        ? "chat-mathjax-block"
-        : $"chat-mathjax-block {this.Class}";
+        ? "formula-block"
+        : $"formula-block {this.Class}";
 
     private string MathText => $"$${Environment.NewLine}{this.Value}{Environment.NewLine}$$";
 }