WIP: Fix Arc::new() wrapping on tool handlers — some import/paren issues remain

Co-Authored-By: Proof of Concept <poc@bcachefs.org>

src/agent/tools/write.rs

@@ -8,7 +8,7 @@ pub fn tool() -> super::Tool {
         name: "write_file",
         description: "Create or overwrite a file with the given content.",
         parameters_json: r#"{"type":"object","properties":{"file_path":{"type":"string","description":"Absolute path to write"},"content":{"type":"string","description":"File content"}},"required":["file_path","content"]}"#,
-        handler: Arc::new(|_a, v| Box::pin(async move { write_file(&v)) }),
+        handler: Arc::new(|_a, v| Box::pin(async move { write_file(&v) })),
     }
 }