78a6758349
Use a 16-byte random salt per encryption instead of the fixed "groombook-auth-provider-config" salt. This prevents identical plaintexts from producing identical ciphertexts, closing the timing/anagram security gap identified in GRO-452. New format: salt:iv:ciphertext:authTag (all base64). Legacy format (iv:ciphertext:authTag) is still accepted for backward-compatible decryption of existing stored values. Co-Authored-By: Paperclip <noreply@paperclip.ing>