refactor: remove the motorcycle

Phase 2 of turning the game into the company landing page.

- Delete the Apache motorcycle model, its BIKE handling spec, the
  motorcycle row in the factory yard, rider and lean animation, and its
  prompt and dialogue strings.
- The garage now holds cars only; the oriented-box collision, traffic
  lane checks and other vehicles are unchanged.
- Rework the vehicle tests to cover gaps with a car instead of a bike,
  and add a check that no motorcycle code or text remains.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/game/runtime/movement.js

@@ -49,18 +49,17 @@ function toggleCar(context) {
 }
 
 /**
- * Gets on or in the closest vehicle within reach, if there is one.
+ * Gets into the closest vehicle within reach, if there is one.
  * @param {object} context - Game context.
  */
 function getIn(context) {
   const ride = nearestRide(context);
   if (!ride) return;
-  const { kind } = takeRide(context, ride);
+  takeRide(context, ride);
   context.mode = 'drive';
-  context.cam.distance = Math.max(context.cam.distance, kind === 'bike' ? 6 : 8);
+  context.cam.distance = Math.max(context.cam.distance, 8);
   context.tone(320, 0.2, 0.05, 'square');
-  const line = kind === 'bike' ? strings.dialogue.bikeOn : strings.dialogue.carOn;
-  context.say('father', line);
+  context.say('father', strings.dialogue.carOn);
 }
 
 /**