- Remove unused mach vm_prot_t type and VM_PROT_* constants
- Remove unused EmailChannel.smtp_config field
- Remove unused AttributionEngine.campaigns field
- Remove unused BehaviorSignature.confidence_threshold field
- Prefix unused DetectionEngine._config with underscore
- Prefix unused MitreAttackEngine._campaigns with underscore
- Prefix unused NeuralMemoryAnalyzer._confidence_threshold with underscore
All tests passing (24 total). Clean build with zero warnings.
bff5b05837