docs: adding API usage examples and testing guide to README

[Dare-TechieZ]

Description

Problem

While reviewing the project documentation, I noticed that the README lists the available API endpoints, but it does not provide examples of how to interact with them.

For new contributors, especially those who are new to Rust and Actix Web, it can be difficult to verify whether the backend is functioning correctly or understand the expected request and response format.

Proposed Solution

I would like to improve the documentation by adding an API Usage & Testing section to the README.

The new section could include:

• Sample requests for each available endpoint using curl.
• Expected JSON responses.
• HTTP status codes returned by each endpoint.
• Instructions for testing the API using tools such as Postman or Insomnia.
• Notes on how future API endpoints should be documented to maintain consistency.

Benefits

• Makes it easier for new contributors to verify their local setup.
• Provides a quick reference for existing API endpoints.
• Improves developer onboarding and reduces confusion.
• Establishes a consistent format for documenting future APIs.

Additional Note

I am a GSSoC'26 contributor and would love to work on this documentation enhancement. If this proposal aligns with the project's goals, I would appreciate being assigned this issue. Thank you!