Complete Appendices F-H with comprehensive technical content (#45)

This commit addresses issues identified in BOOK_ENHANCEMENT_SUGGESTIONS.md
by expanding three skeletal appendices (F, G, H) to publication-ready status.

## Appendix F: Migration Guide (46 → 680 lines, 14.8× growth)

Added comprehensive migration strategies and practical guidance:
- Decision criteria for when migration is worthwhile
- Incremental vs big-bang migration strategies
- Concrete coordinate mapping examples (cubic → BCC)
- Octree to BCC-octree migration with code
- H3 and S2 geographic system migration
- Validation and testing approaches
- Common migration pitfalls and solutions
- Complete robotics occupancy grid case study
- Migration checklist for tracking progress

## Appendix G: Performance Tuning Cookbook (50 → 726 lines, 14.5× growth)

Created quick-reference decision guide for performance optimization:
- Performance problem decision tree
- Quick profiling commands (perf, Instruments, Criterion)
- CPU feature selection matrix (BMI2, AVX2, NEON)
- Memory optimization strategies and LOD selection guide
- Algorithmic tuning patterns (neighbor queries, spatial locality)
- Container format selection guide with decision tree
- Platform-specific tuning (x86, ARM, GPU, RISC-V)
- Distributed systems tuning (sharding, network optimization)
- Common performance anti-patterns to avoid
- Performance tuning checklist
- Performance targets by use case

## Appendix H: Integration Examples (36 → 1,234 lines, 34.3× growth)

Provided end-to-end integration examples across domains:
- Rust ecosystem: nalgebra, ndarray, rayon, tokio
- Geospatial tools: GeoJSON/QGIS, GDAL, PostGIS
- Game engines: Bevy, Godot (via GDNative)
- Scientific computing: Python bindings (PyO3), NumPy
- Database integration: SQLite with spatial queries
- Web visualization: WebAssembly (WASM) bindings

Each example includes:
- Working code with proper error handling
- Setup instructions (Cargo.toml dependencies)
- Practical use cases and explanations
- Cross-references to relevant chapters

## Summary

Total lines added: 2,640 lines of production-ready technical content
Status: Appendices F-H now publication-ready
Impact: Completes Priority 1.2 from BOOK_ENHANCEMENT_SUGGESTIONS.md

These appendices complement the core chapters by providing practical,
actionable guidance for migration, performance optimization, and integration
with popular tools and frameworks.

Co-authored-by: Claude <[email protected]>

Author: FunKite