- Add `SymmetricallyDecrypt` to `pkg/crypt/std/pgp`.
- Add validation for empty passphrases in `SymmetricallyEncrypt` and `SymmetricallyDecrypt`.
- Refactor `pkg/crypt/std/pgp/pgp.go` to use package-level variables for `openpgp` functions to enable mocking.
- Add comprehensive tests in `pkg/crypt/std/pgp/pgp_test.go` to cover error paths using mocks, achieving 100% coverage.
- Remove practically unreachable error check in `GenerateKeyPair` for `SignUserId` (as `NewEntity` guarantees validity).
Expands the existing OpenPGP implementation to include a more complete set of features for handling PGP data.
- Adds support for signing and verifying detached signatures.
- Adds support for symmetric encryption using a passphrase.
- Includes tests for all new functionality.
Adds a full implementation of OpenPGP features using ProtonMail's go-crypto fork.
- Implements PGP key generation, encryption, and decryption.
- Exposes PGP functionality through the crypt.Service.
- Adds tests for the PGP implementation.
