Let an agent holding only EMCLI_KEY discover accounts via `account list`,
exposing name/from/can_send (not host/username); admin keeps the full
text table. account add/edit/remove stay admin-only.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Enforce the agent/admin trust boundary with two env keys (EMCLI_ADMIN_KEY,
EMCLI_KEY) via envelope encryption: one DEK wrapped per role. Admin commands
unwrap the admin slot only (no agent fallback), so a forced agent holding
EMCLI_KEY cannot authorize config changes.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>