Backend: Add Unit Tests

Description:

Implement unit tests for critical backend components to ensure code reliability, maintainability, and prevent regressions.

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Tasks:

1. Unit Tests for Main Application

   • Add tests for cmd/main_test.go to validate application startup and initialization.

2. Unit Tests for Configuration

   • Implement tests in config/main_test.go to verify configuration loading and environment variable handling.

3. Unit Tests for API Layer

   • Create tests in pkg/api/main_test.go to cover API request handling.
   • Add tests in pkg/api/neuvector_test.go for NeuVector API interactions.

4. Unit Tests for Collector Services

   • Implement tests in pkg/collector/main_test.go for data collection workflows.
   • Add tests for pkg/collector/neuvector_collector.go to validate integration with NeuVector.

5. Mocking and Error Handling

   • Use mock dependencies for external API calls.
   • Ensure proper error handling scenarios are covered.

6. Run Tests

   • Ensure tests pass locally
   • Measure test coverage and improve where necessary.