- Added `config.py` for centralized configuration management including Sync, API, Advoware, EspoCRM, Redis, Logging, Calendar Sync, and Feature Flags.
- Created `exceptions.py` with a hierarchy of custom exceptions for integration errors, API errors, sync errors, and Redis errors.
- Developed `logging_utils.py` for a unified logging wrapper supporting structured logging and performance tracking.
- Defined Pydantic models in `models.py` for data validation of Advoware and EspoCRM entities, including sync operation models.
- Introduced `redis_client.py` for a centralized Redis client factory with connection pooling, automatic reconnection, and health checks.