sessions.rs (1 730 lines) becomes sessions/ with mod.rs (types, session lifecycle, I/O, recording, tests), credentials.rs (secret resolution, prompts, host-key checks), protocols.rs (SSH, GitHub, IRC, VNC, RDP connects and SSH tunnels), local.rs (local shells, login scripts) and extras.rs (per-protocol accessors). Code moves unchanged; helpers that crossed a module boundary became pub(super).