Rework of the file export (#894)

Co-authored-by: Thorsten Sommer <SommerEngineering@users.noreply.github.com>

app/MindWork AI Studio/Tools/FileExportFormat.cs

@@ -0,0 +1,18 @@
+namespace AIStudio.Tools;
+
+/// <summary>
+/// The file formats a chat message can be exported to.
+/// </summary>
+public enum FileExportFormat
+{
+    NONE,
+    UNKNOWN,
+
+    MICROSOFT_WORD,
+    OPEN_DOCUMENT_TEXT,
+    LATEX,
+    MARKDOWN,
+    HTML,
+    CSV,
+    TSV,
+}