Add complete transit engine supporting symmetric encryption (AES-256-GCM,
XChaCha20-Poly1305), asymmetric signing (Ed25519, ECDSA P-256/P-384),
and HMAC (SHA-256/SHA-512) with versioned key rotation, min decryption
version enforcement, key trimming, batch operations, and rewrap.
Includes proto definitions, gRPC handlers, REST routes, and comprehensive
tests covering all 18 operations, auth enforcement, and edge cases.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Kyle Isom
cbd77c58e8