fix(repair): keep ebike at zone Y in test scene

Adds an opt-out 'snapToTerrain' prop on Ebike so the parked position
keeps the explicit Y supplied by callers instead of resolving against
the world terrain GLTF. TestMap passes snapToTerrain={false} since it
does not render the world terrain — without this the bike was being
positioned at the invisible terrain height, far above the test floor,
and looked missing.

src/components/ebike/Ebike.tsx

@@ -33,9 +33,19 @@ const _up = new THREE.Vector3(0, 1, 0);
 
 interface EbikeProps {
   position: Vector3Tuple;
+  /**
+   * When true (default), the parked position is snapped to the world terrain
+   * height. Pass false in test scenes that don't render the world terrain so
+   * the bike stays at the explicit Y of {@link position} instead of floating
+   * at the (invisible) terrain height.
+   */
+  snapToTerrain?: boolean;
 }
 
-export function Ebike({ position }: EbikeProps): React.JSX.Element {
+export function Ebike({
+  position,
+  snapToTerrain = true,
+}: EbikeProps): React.JSX.Element {
   const groupRef = useRef<THREE.Group>(null);
   const { scene } = useLoggedGLTF(EBIKE_MODEL_PATH, {
     scope: "Ebike",
@@ -45,7 +55,7 @@ export function Ebike({ position }: EbikeProps): React.JSX.Element {
   const terrainHeight = useTerrainHeightSampler();
   const parkedPosition = useMemo<Vector3Tuple>(() => {
     const [x, y, z] = position;
-    const height = terrainHeight.getHeight(x, z) ?? y;
+    const height = snapToTerrain ? (terrainHeight.getHeight(x, z) ?? y) : y;
     const bottomOffset = getObjectBottomOffset(model, [
       EBIKE_WORLD_SCALE,
       EBIKE_WORLD_SCALE,
@@ -53,7 +63,7 @@ export function Ebike({ position }: EbikeProps): React.JSX.Element {
     ]);
 
     return [x, height + bottomOffset, z];
-  }, [model, position, terrainHeight]);
+  }, [model, position, snapToTerrain, terrainHeight]);
   const movementMode = useGameStore((state) => state.player.movementMode);
   const mainState = useGameStore((state) => state.mainState);
   const ebikeStep = useGameStore((state) => state.ebike.currentStep);
@@ -135,7 +145,9 @@ export function Ebike({ position }: EbikeProps): React.JSX.Element {
   // SpotLight target must be in the scene to define the cone direction.
   useEffect(() => {
     threeScene.add(headlightTarget);
-    return () => { threeScene.remove(headlightTarget); };
+    return () => {
+      threeScene.remove(headlightTarget);
+    };
   }, [threeScene, headlightTarget]);
 
   // Link the target to the SpotLight once it mounts.
@@ -192,7 +204,9 @@ export function Ebike({ position }: EbikeProps): React.JSX.Element {
       console.log("[Ebike] Fork found:", (forkNode as THREE.Object3D).name);
     } else {
       const names: string[] = [];
-      model.traverse((c) => { if (c.name) names.push(c.name); });
+      model.traverse((c) => {
+        if (c.name) names.push(c.name);
+      });
       console.warn("[Ebike] Fork not found. All nodes:", names);
     }
   }, [model]);
@@ -222,11 +236,11 @@ export function Ebike({ position }: EbikeProps): React.JSX.Element {
   useFrame((_, delta) => {
     // ── SpotLight headlight — tune the constants below ────────────────────────
     // ── SpotLight headlight — tune these four constants ───────────────────────
-    const LIGHT_OFFSET_X   =  -0.7;   // position : left(-) / right(+)
-    const LIGHT_OFFSET_Y   =  1.5;   // position : down(-) / up(+)
-    const LIGHT_OFFSET_Z   =  0;   // position : backward(-) / forward(+)
-    const LIGHT_AIM_DEG    = 90;  // aim rotation around Y : 0=forward, -90=left, +90=right
-    const LIGHT_TARGET_DIST = 20;  // metres devant la position de la lumière
+    const LIGHT_OFFSET_X = -0.7; // position : left(-) / right(+)
+    const LIGHT_OFFSET_Y = 1.5; // position : down(-) / up(+)
+    const LIGHT_OFFSET_Z = 0; // position : backward(-) / forward(+)
+    const LIGHT_AIM_DEG = 90; // aim rotation around Y : 0=forward, -90=left, +90=right
+    const LIGHT_TARGET_DIST = 20; // metres devant la position de la lumière
     // ─────────────────────────────────────────────────────────────────────────
     if (headlightRef.current && phareRef.current && groupRef.current) {
       phareRef.current.getWorldPosition(_phareWorldPos);
@@ -460,7 +474,11 @@ export function Ebike({ position }: EbikeProps): React.JSX.Element {
           >
             <mesh>
               <sphereGeometry args={[8, 15, 12]} />
-              <meshBasicMaterial colorWrite={false} color={"red"} depthWrite={false} />
+              <meshBasicMaterial
+                colorWrite={false}
+                color={"red"}
+                depthWrite={false}
+              />
             </mesh>
           </InteractableObject>
 
@@ -469,7 +487,12 @@ export function Ebike({ position }: EbikeProps): React.JSX.Element {
               Speedmeter: upper-half arc overlay, renderOrder 10 001
               rotation: Math.PI/2 radians = 90° (NOT the number 90 which = ~116.6°) */}
           <group position={[2, 6, 0]} rotation={[0, -80, 0]}>
-            <EbikeSpeedmeter width={3} height={1.5} position={[0, 0.4, 0]} gaugeInnerR={0.33} gaugeOuterR={0.445}
+            <EbikeSpeedmeter
+              width={3}
+              height={1.5}
+              position={[0, 0.4, 0]}
+              gaugeInnerR={0.33}
+              gaugeOuterR={0.445}
               gaugeWidth={2.5}
               gaugeHeight={2.1}
               gaugeOffsetX={0}
@@ -499,8 +522,8 @@ export function Ebike({ position }: EbikeProps): React.JSX.Element {
           ref={headlightRef}
           intensity={100}
           color="#ffca60"
-          angle={Math.PI / 5}   // 22.5° demi-angle — cone étroit comme une torche
-          penumbra={0.5}        // bord doux (0 = dur, 1 = très doux)
+          angle={Math.PI / 5} // 22.5° demi-angle — cone étroit comme une torche
+          penumbra={0.5} // bord doux (0 = dur, 1 = très doux)
           distance={50}
           decay={2.5}
           castShadow={false}