docs: Add Claude Desktop Integration Guide and README

- Comprehensive Claude Desktop integration documentation
- 5 MCP tools with usage examples and tips
- 3 MCP resources (quantum state, KG-Index, manifests)
- Performance benchmarks and troubleshooting guide
- Commands, tips & tricks for optimal usage

Key Features Documented:
- Quantum hash (1,796 hashes/sec)
- Merkle tree construction (1,262 leaves/sec)
- Signed manifests with quantum attestation
- KG-Index queries (288 nodes, 6 contexts)
- T4 GPU offload (5.5x speedup)

Files Added:
- CLAUDE_DESKTOP_README.md (GitHub integration guide)
- CLAUDE_DESKTOP_GUIDE.md (commands & advanced usage)

Author: Yennefer