Module handoff

Expand description

Handoff typestate for compile-time safety of handoff lifecycle.

Uses the typestate pattern to make invalid state transitions uncompilable.

§State Transition Diagram

create() → Initiated ──┬── accept() ──→ Accepted ── complete() → Completed
                       └── reject() ──→ Rejected (terminal)

Handoff: A handoff with compile-time state tracking.
HandoffAccepted: Handoff was accepted by the receiving agent.
HandoffCompleted: Handoff has been completed (terminal).
HandoffRecord: Internal data storage for a handoff, independent of typestate. This is what gets persisted to the database.
Initiated: Handoff has been initiated, waiting for acceptance.
Rejected: Handoff was rejected by the receiving agent (terminal).
StoredHandoff: A handoff as stored in the database (status-agnostic).

HandoffStateError: Errors when transitioning handoff states.
HandoffStatus: Status of a handoff operation.
LoadedHandoff: Enum representing all possible runtime states of a handoff. Use this when you need to handle handoffs loaded from the database.