agent2: Clean up tool descriptions (#36619)

schemars was passing along the newlines from the doc comments. This
should make these closer to the markdown file versions we had in the old
agent.

Release Notes:

- N/A

crates/agent2/src/tools/delete_path_tool.rs

@@ -9,8 +9,7 @@ use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 use std::sync::Arc;
 
-/// Deletes the file or directory (and the directory's contents, recursively) at
-/// the specified path in the project, and returns confirmation of the deletion.
+/// Deletes the file or directory (and the directory's contents, recursively) at the specified path in the project, and returns confirmation of the deletion.
 #[derive(Debug, Serialize, Deserialize, JsonSchema)]
 pub struct DeletePathToolInput {
     /// The path of the file or directory to delete.