fix: supply client version for cart operations

PicNic suddenly requires a client version
for cart operations.

Author: codesalatdev

src/python_picnic_api2/client.py

@@ -176,7 +176,7 @@ def search(self, term: str) -> SearchResult:
         return SearchResult.from_page(raw_results)
 
     def get_cart(self) -> Cart:
-        return Cart.from_api(self._get("/cart"))
+        return Cart.from_api(self._get("/cart", add_picnic_headers=True))
 
     def get_article(self, article_id: str, add_category=False) -> Article | None:
         path = f"/pages/product-details-page-root?id={article_id}" + \
@@ -212,14 +212,14 @@ def get_article_category(self, article_id: str):
 
     def add_product(self, product_id: str, count: int = 1) -> Cart:
         data = {"product_id": product_id, "count": count}
-        return Cart.from_api(self._post("/cart/add_product", data))
+        return Cart.from_api(self._post("/cart/add_product", data, add_picnic_headers=True))
 
     def remove_product(self, product_id: str, count: int = 1) -> Cart:
         data = {"product_id": product_id, "count": count}
-        return Cart.from_api(self._post("/cart/remove_product", data))
+        return Cart.from_api(self._post("/cart/remove_product", data, add_picnic_headers=True))
 
     def clear_cart(self) -> Cart:
-        return Cart.from_api(self._post("/cart/clear"))
+        return Cart.from_api(self._post("/cart/clear", add_picnic_headers=True))
 
     def get_delivery_slots(self) -> DeliverySlots:
         return DeliverySlots.from_api(self._get("/cart/delivery_slots"))