…, Developer Tools

## New Modules (17 new files across 4 module groups)

### AI/ML Enhanced (ai_enhanced/)
- inference_engine.rs: High-performance ML model inference
- federated_learning.rs: Privacy-preserving distributed training
- model_optimizer.rs: Neural network optimization (quantization, pruning)
- anomaly_detection.rs: Real-time system anomaly detection
- resource_predictor.rs: Predictive resource management

### Enhanced Networking (networking_enhanced/)
- sdn_controller.rs: Software-Defined Networking controller
- traffic_shaper.rs: Token bucket-based traffic shaping
- zero_trust_network.rs: Zero-trust security model

### Enhanced Security (security_enhanced/)
- runtime_integrity.rs: Continuous runtime integrity monitoring
- secure_enclave.rs: Hardware-backed secure enclave

### Developer Tools (developer_tools/)
- profiler.rs: Comprehensive system profiler
- debugger.rs: Kernel-level debugger
- build_system.rs: Integrated build system

## Bug Fixes
- Fixed rand 0.10 API compatibility (RngCore, thread_rng)
- Fixed unstable is_multiple_of() in allocator
- Fixed borrow checker issues in new modules
- Fixed closure type inference in SDN controller

## Version bump: 1.2.0 -> 1.6.0
All modules compile cleanly with cargo check on stable Rust 1.85.0

Phase 2 - Documentation:
- Update ROADMAP.md with v1.6.0 milestone completion
- Update README.md with v1.6.0 Enhanced Features
- Create comprehensive V1_6_0_ENHANCED_FEATURES_GUIDE.md

Phase 3 - Integration Tests (tests_v1_6_0_integration.rs):
- 50+ unit tests across all v1.6.0 modules
- AI module tests: anomaly detection, inference engine, federated learning,
  model optimizer, resource predictor
- Networking tests: SDN controller, traffic shaper, zero trust network
- Security tests: integrity monitor, secure enclave lifecycle & crypto
- Developer tools tests: profiler, debugger, build system
- Cross-module integration tests: anomaly->prediction pipeline,
  traffic shaping with profiling, integrity-protected enclaves,
  full system scenario

Phase 3 - Benchmarks (benches_v1_6_0.rs):
- Inference engine: model load throughput, tensor ops, session latency
- Traffic shaper: packet throughput, burst handling, multi-class
- Anomaly detection: observation throughput (zscore & EWMA)
- SDN controller: topology scaling, flow installation throughput
- Zero trust: evaluation throughput with 100 identities
- Secure enclave: crypto operations, key generation
- Integrity monitor: scaling to 200 resources, full check
- Model optimizer: large model optimization
- Federated learning: multi-round training
- Resource predictor: continuous observation & prediction
- Profiler: span overhead measurement
- Build system: dependency resolution, full build