Update status of all epic0 stories (0.1-0.5) from Pending to Completed:
- 0.1: Project Initialization - Directory structure and Go module setup
- 0.2: Configuration Management System - Viper-based config implemented
- 0.3: Structured Logging System - Zap logger with middleware implemented
- 0.4: CI/CD Pipeline - GitHub Actions workflow with tests and linting
- 0.5: DI and Bootstrap - FX-based DI container with lifecycle management
All stories have been implemented with tests and are working.
