refactor: remove reference-only implementations and buggy code BREAKING CHANGE: Removed non-production code for security and clarity Removed implementations: - Post-quantum cryptography (Kyber, Dilithium, SPHINCS+) - Protocol implementations (Noise, Signal, OTR, OPAQUE) - Zero-knowledge proofs (Groth16, Ring Signatures) - Hardware security stubs (PKCS#11, Azure Key Vault, TPM) - Buggy hardware acceleration code (FieldArithmetic.cs with buffer overflows)#34