fix: Reorder API routes and update main page layout

- Move /makers/ and /models/ routes before /{car_id} to fix route conflict
- Center Request Vehicle button, move PromoPreference to the right

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/api/cars.py

@@ -122,6 +122,54 @@ def get_cars(
     )
 
 
+# Makers - Must be defined before /{car_id} to avoid route conflict
+@router.get("/makers/", response_model=List[CarMakerResponse])
+def get_makers(db: Session = Depends(get_db)):
+    """제조사 목록 조회"""
+    return db.query(CarMaker).all()
+
+
+@router.post("/makers/", response_model=CarMakerResponse)
+def create_maker(maker_data: CarMakerCreate, db: Session = Depends(get_db)):
+    """제조사 등록"""
+    existing = db.query(CarMaker).filter(CarMaker.code == maker_data.code).first()
+    if existing:
+        return existing
+
+    maker = CarMaker(**maker_data.dict())
+    db.add(maker)
+    db.commit()
+    db.refresh(maker)
+    return maker
+
+
+# Models - Must be defined before /{car_id} to avoid route conflict
+@router.get("/models/", response_model=List[CarModelResponse])
+def get_models(maker_id: Optional[int] = None, db: Session = Depends(get_db)):
+    """모델 목록 조회"""
+    query = db.query(CarModel)
+    if maker_id:
+        query = query.filter(CarModel.maker_id == maker_id)
+    return query.all()
+
+
+@router.post("/models/", response_model=CarModelResponse)
+def create_model(model_data: CarModelCreate, db: Session = Depends(get_db)):
+    """모델 등록"""
+    existing = db.query(CarModel).filter(
+        CarModel.code == model_data.code,
+        CarModel.maker_id == model_data.maker_id
+    ).first()
+    if existing:
+        return existing
+
+    model = CarModel(**model_data.dict())
+    db.add(model)
+    db.commit()
+    db.refresh(model)
+    return model
+
+
 @router.get("/{car_id}", response_model=CarResponse)
 def get_car(car_id: int, admin: bool = Query(False), db: Session = Depends(get_db)):
     """차량 상세 조회"""
@@ -295,54 +343,6 @@ def delete_car(car_id: int, db: Session = Depends(get_db)):
         raise HTTPException(status_code=500, detail=f"Delete failed: {str(e)}")
 
 
-# Makers
-@router.get("/makers/", response_model=List[CarMakerResponse])
-def get_makers(db: Session = Depends(get_db)):
-    """제조사 목록 조회"""
-    return db.query(CarMaker).all()
-
-
-@router.post("/makers/", response_model=CarMakerResponse)
-def create_maker(maker_data: CarMakerCreate, db: Session = Depends(get_db)):
-    """제조사 등록"""
-    existing = db.query(CarMaker).filter(CarMaker.code == maker_data.code).first()
-    if existing:
-        return existing
-
-    maker = CarMaker(**maker_data.dict())
-    db.add(maker)
-    db.commit()
-    db.refresh(maker)
-    return maker
-
-
-# Models
-@router.get("/models/", response_model=List[CarModelResponse])
-def get_models(maker_id: Optional[int] = None, db: Session = Depends(get_db)):
-    """모델 목록 조회"""
-    query = db.query(CarModel)
-    if maker_id:
-        query = query.filter(CarModel.maker_id == maker_id)
-    return query.all()
-
-
-@router.post("/models/", response_model=CarModelResponse)
-def create_model(model_data: CarModelCreate, db: Session = Depends(get_db)):
-    """모델 등록"""
-    existing = db.query(CarModel).filter(
-        CarModel.code == model_data.code,
-        CarModel.maker_id == model_data.maker_id
-    ).first()
-    if existing:
-        return existing
-
-    model = CarModel(**model_data.dict())
-    db.add(model)
-    db.commit()
-    db.refresh(model)
-    return model
-
-
 # ==================== Soldout APIs ====================
 
 @router.post("/{car_id}/soldout")