Created test suite for Relay entity covering construction, state toggling,
and explicit state control methods. Tests intentionally fail as Relay
struct is not yet implemented.
Tests cover:
- Relay::new() with id, state, and optional label
- toggle() flipping state between On/Off
- turn_on() setting state to On
- turn_off() setting state to Off
TDD phase: RED - Tests written, implementation pending (T022)
Ref: T021 (specs/001-modbus-relay-control/tasks.md)
Lucien Cartier-Tilet
72eafd285b
