[Enhancement] Add docstring with description, params, and return

[Dario0731]

🛠 Issue: Add docstring with description, params, and return

📌 Description

Add docstring with description, params, and return on every function on: src\objectives\objectives.controller.ts
Use the next template:

/*

• Brief description: explains what the function does.
• @param {Type} param1 - Explanation of the first parameter (If needed).
• @param {Type} param2 - Explanation of the second parameter (If needed).
• @returns {Promise} What the function returns, with description of the resolved value or rejection reason.
• @throws {Error} (Optional) Description of possible thrown errors.
  */