마무리 한 수정사항

[o] /api/v1/products/category?categoryId={id} ⇒ /api/v1/categories/{categoryId}
[o] /api/v1/products/{productId} → {product_code}
[o] /api/v1/products/{productId}/reviews → {product_code}/reviews
[o] /api/v1/products/{product_code}/photos → /api/v1/products/{product_code}/photo-reviews
[o] /api/v1/products/{productId} → /{product_code}
[o] /api/v1/products/{product_코드}/reviews : 리뷰 작성, 수정, 삭제 [post, put, delete]