Security:
- Versioned, self-describing payload format (v2) that stores KDF
parameters, enabling future crypto agility
- Upgrade key derivation to PBKDF2-HMAC-SHA512 at 600k iterations
(was SHA256 at 200k)
- Bind the full header (prefix, version, KDF params, salt, nonce)
into the AES-GCM tag as associated data so header tampering is detected
- Zero derived keys and secret bytes from memory after use
- Enforce a minimum combined key length
- Keep backwards-compatible decryption for legacy v1 payloads
UX:
- Add a Generate button that creates a strong random key with a
transcription-friendly alphabet
- Add a Show/Hide keys toggle
- Add a live key-strength indicator
- Replace leftover Dutch file-dialog strings with English