The menu hierarchy is not displayed correctly

Problem/Motivation

The module currently fails to generate the correct hierarchical structure for menus in the llms.txt file.

Instead of traversing the menu tree recursively, the module seems to be rendering items sequentially by depth/weight. This results in child items being visually appended to the last parent rendered of the previous level, rather than their actual parent.

Drupal menu:

Llms.txt:

Steps to reproduce

1. Create a Main Menu structure with at least two parent items.
2. Add a child item to the first parent item.
3. Leave the second parent item without children.
4. Generate/view the llms.txt file.
5. Observe that the child of the first parent is rendered indented under the second parent.

Example scenario:

- Parent Item 1
  -- Child Item A
- Parent Item 2

Current output in llms.txt:

- [Parent Item 1](url)
- [Parent Item 2](url)
  - [Child Item A](url)  <-- INCORRECT: It appears as a child of Parent 2

Proposed resolution

The rendering logic needs to be refactored to traverse the menu tree properly.