b08b388d5d
Add SecondFactor enum (Image | Keyfile, serde lowercase) to relicario-core::crypto, re-export from lib.rs alongside KdfParams. Add #[serde(default)] second_factor field to ParamsFile in relicario-cli::session so existing params.json files (no field) still parse as Image. for_new_vault() initialises the field to Image. No unlock logic changed; that is deferred to Task 4. TDD: tests written RED first, then GREEN. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01McMF5pUJbCMricmFEnf2sG