Allowed reading plain text and JSON from the web, with a stronger prompt injection filter (#1000)

app/MindWork AI Studio/Tools/Web/WebContentKind.cs

@@ -0,0 +1,19 @@
+namespace AIStudio.Tools.Web;
+
+/// <summary>
+/// What a retrieved web resource turned out to be, which decides how its content was read.
+/// </summary>
+public enum WebContentKind
+{
+    /// <summary>
+    /// An HTML page. Its readable part was extracted and converted to Markdown, so the content
+    /// can be shorter than the page when the extraction missed something.
+    /// </summary>
+    HTML_PAGE,
+
+    /// <summary>
+    /// A text document such as plain text, JSON, XML, or CSV. The extracted Markdown is its text
+    /// as the server sent it, so nothing of it was left out.
+    /// </summary>
+    TEXT_DOCUMENT,
+}