Crosswalk lights

A pedestrian button is added to a car light that already cycles on its own timer. The walk signal should only be on while the car light is red, but granting the walk never checks the car light. Press the button while cars have green, and both go at once.

// spec.ts (shortened)
{
  name: 'grant walk',
  // The bug: never checks that the car light is red.
  guard: (s) => s.requested && s.walkSignal === 'dontwalk',
  effect: (s) => ({ ...s, walkSignal: 'walk', requested: false }),
},

See how SpecCraft TS finds and fixes it.