Implement Unit Tests for Core Components

Description
The project currently does not include unit tests, which are essential for ensuring code reliability and simplifying future development.

Suggested Action
Create unit tests for key components including:

• FastAPI endpoints: verify that API routes return the expected responses.
• Data processing functions: validate data handling and transformations.
• Integration points: ensure proper integration with Prometheus and Grafana.

Benefit
Adding unit tests will improve code quality, make debugging easier, and allow safer modifications in the future.