style: 修正新测试的格式以符合 rustfmt 宽度限制

cargo fmt 自动调整了 highlight.rs 与 error.rs 中新增测试的
assert! / assert_eq! 长行折行。

src/api/error.rs

@@ -121,7 +121,10 @@ mod tests {
         let err: ServerFnError = AppError::tx("deadlock detected on UPDATE posts").into();
         let msg = err.to_string();
         assert!(!msg.contains("UPDATE"), "should not leak SQL: {msg}");
-        assert!(!msg.contains("deadlock"), "should not leak error detail: {msg}");
+        assert!(
+            !msg.contains("deadlock"),
+            "should not leak error detail: {msg}"
+        );
         assert!(msg.contains("操作失败"), "expected generic message: {msg}");
     }
 

src/highlight.rs

@@ -215,7 +215,9 @@ mod tests {
         let result = highlight_code(code, Some("rust"));
         // 两处 fn 关键字都应出现
         assert_eq!(
-            result.matches(r#"<span class="storage type function rust">fn</span>"#).count(),
+            result
+                .matches(r#"<span class="storage type function rust">fn</span>"#)
+                .count(),
             2
         );
     }