feat: require reading the service description before purchase

For categories with has_extra_description, the buy button now stays
disabled until the user ticks "توضیحات سرویس را مطالعه کردم" — mirrors
the pattern used for the Shahkar/advanced-verification gates.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/pages/shop/section/productList/components/ModalBuy.tsx

@@ -47,6 +47,7 @@ const ModalBuy = ({ isOpen, setIsOpen, configId }: ModalBuyProps) => {
   const [isInfoOpen, setIsInfoOpen] = useState(false);
   const [needsShahkarVerification, setNeedsShahkarVerification] = useState(false);
   const [nationalCode, setNationalCode] = useState("");
+  const [hasReadDescription, setHasReadDescription] = useState(false);
   const payablePrice = toNumber(
     price === 0 ? data?.data?.result?.price || 0 : price
   );
@@ -103,6 +104,7 @@ const ModalBuy = ({ isOpen, setIsOpen, configId }: ModalBuyProps) => {
      setPrice(0);
      setNeedsShahkarVerification(false);
      setNationalCode("");
+     setHasReadDescription(false);
    }
  }, [isOpen, setFieldValue]);
   const mutation = useMutation({
@@ -194,6 +196,11 @@ const ModalBuy = ({ isOpen, setIsOpen, configId }: ModalBuyProps) => {
      return;
    }
 
+   if (hasExtraDescription && !hasReadDescription) {
+     toast.error("لطفا ابتدا توضیحات سرویس را مطالعه و تایید کنید");
+     return;
+   }
+
    if (needsShahkarVerification && nationalCode.trim().length !== 10) {
      toast.error("لطفا کد ملی ۱۰ رقمی را به‌درستی وارد کنید");
      return;
@@ -282,7 +289,8 @@ const ModalBuy = ({ isOpen, setIsOpen, configId }: ModalBuyProps) => {
      submitOnClick={submitHandler}
      disabled={
        isLoading ||
-       isFetching
+       isFetching ||
+       (hasExtraDescription && !hasReadDescription)
      }
      nameService={
         isLoading || isFetching
@@ -337,6 +345,17 @@ const ModalBuy = ({ isOpen, setIsOpen, configId }: ModalBuyProps) => {
                 توضیحات سرویس
               </Button>
             )}
+            {hasExtraDescription && (
+              <label className="w-full flex flex-row-reverse items-center gap-2 text-xs md:text-sm text-gray-300 cursor-pointer select-none">
+                <input
+                  type="checkbox"
+                  checked={hasReadDescription}
+                  onChange={(e) => setHasReadDescription(e.target.checked)}
+                  className="w-4 h-4 accent-secondTheme"
+                />
+                توضیحات سرویس را مطالعه کردم
+              </label>
+            )}
             <Alert type="danger">
               {" "}
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