add load testing

[GabrielVGS]

Is your feature request related to a problem? Please describe.
Currently, there are no load tests configured in the project. This makes it difficult to identify performance bottlenecks and understand how the system behaves under high volumes of concurrent requests.

Describe the solution you'd like
Add automated load testing (e.g., using tools like Locust, k6, or JMeter) that can be easily run locally and/or integrated into the CI/CD pipeline. These tests should simulate real-world scenarios, including multiple users and different endpoints.

Checklist

• Research and decide on a load testing tool (Locust, k6, JMeter, etc.)
• Set up a basic load test scenario for core endpoints
• Configure test parameters (concurrent users, request rate, duration)
• Add documentation on how to run load tests locally
• Integrate load tests into CI/CD pipeline (optional/advanced)
• Analyze and document results for future benchmarking