Improved docx and odt import (#890)

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

app/MindWork AI Studio/Tools/ContentStreamPptxImageData.cs

@@ -15,4 +15,7 @@ public sealed class ContentStreamPptxImageData
 
     [JsonPropertyName("is_end")] 
     public bool IsEnd { get; init; }
-}
+
+    [JsonPropertyName("media_type")]
+    public string? MediaType { get; init; }
+}