This addresses issue #416 by adding comprehensive unit tests for the
config utility functions:
- TestValidate: Tests validation logic for MinInstances/MaxInstances,
Workers count, ConnectionPooler instances, and user conflicts
- TestNewFromMap: Tests config creation from map with defaults,
custom values, duration/boolean/map/slice parsing, and panic behavior
- TestMain: Sets OPERATOR_NAMESPACE env var for testing outside K8s
The tests cover both valid configurations and error cases.