Refactor markdown formatting utilities to avoid building intermediate strings (#29511)

These were nearly always used when using `format!` / `write!` etc, so it
makes sense to not have an intermediate `String`.

Release Notes:

- N/A

crates/assistant_tools/src/open_tool.rs

@@ -8,7 +8,7 @@ use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 use std::sync::Arc;
 use ui::IconName;
-use util::markdown::MarkdownString;
+use util::markdown::MarkdownEscaped;
 
 #[derive(Debug, Serialize, Deserialize, JsonSchema)]
 pub struct OpenToolInput {
@@ -41,7 +41,7 @@ impl Tool for OpenTool {
 
     fn ui_text(&self, input: &serde_json::Value) -> String {
         match serde_json::from_value::<OpenToolInput>(input.clone()) {
-            Ok(input) => format!("Open `{}`", MarkdownString::escape(&input.path_or_url)),
+            Ok(input) => format!("Open `{}`", MarkdownEscaped(&input.path_or_url)),
             Err(_) => "Open file or URL".to_string(),
         }
     }