[feat: backend] validation middleware for needs requests

[therealjustinbiele]

Description

As a developer, I need to create a middleware function to validate the request body when creating a new "Need" item, ensuring that the request contains the required fields: title, description, and zip code. This validation middleware will help maintain data integrity and consistency within the application.

Acceptance Criteria

• Define a middleware function to validate the request body when creating a new "Need" item.
• Implement validation logic to ensure the request body contains the following fields: title, description, and zip code.
• Validate that each field is present in the request body and is not empty or null.
• Implement additional validation rules as necessary (e.g., length restrictions, data type validation).
• Return an error response with the appropriate status code and message if the request body fails validation.
• Integrate the validation middleware into the route handler for creating "Need" items.
• Test the validation middleware thoroughly with both valid and invalid request payloads.
• Ensure error messages provide clear guidance on missing or invalid fields to aid frontend development and debugging.
• Document the validation middleware function, including its purpose, input requirements, and usage guidelines.
• Ensure the validation middleware is properly integrated and functioning in the backend application.
• Coordinate with the frontend team to ensure consistent handling of validation errors on the client side.

Testing

• Use Postman to send a POST request containing the "Need" data needed to create a new "Need" document.
• Omit the title, description, or the zip to ensure the middleware rejects the request with a 400 bad data.
• Ensure the middleware passes the request to the controller if the fields are present and correct.