honor content_format clientcap

This removes all markdown when the client does not support the markdown MarkupKind

Otherwise the output on the editor will have some markdown boilerplate, making it less readable

crates/ide/src/markdown_remove.rs

@@ -0,0 +1,16 @@
+use pulldown_cmark::{Event, Parser};
+
+pub fn remove_markdown(markdown: &str) -> String {
+    let mut out = String::new();
+    let parser = Parser::new(markdown);
+
+    for event in parser {
+        match event {
+            Event::Text(text) | Event::Code(text) => out.push_str(&text),
+            Event::SoftBreak | Event::HardBreak | Event::Rule => out.push('\n'),
+            _ => {}
+        }
+    }
+
+    out
+}