Add shopping cart, store-items pages, contact form toast; skip workshops+portfolio

Neither workshops nor portfolio is in this tenant's enabledModules
(["products","blog","finance"]) - same reasoning as before, page/nav entry
withheld until either is actually enabled.

Shopping cart (new):
- CartProvider (client context): live cart state, add/update/remove/refresh,
  reads AUTH_TOKEN_COOKIE, calls the real /businesses/{id}/cart* endpoints
  (bearer-only, no guest cart - by design, not a gap)
- CartButton: header/bottom-nav icon with a live count badge and a popup
  preview; "ادامه" hands off to the customer portal's own cart/checkout,
  since this storefront has no checkout UI (address/payment) to hand off to
  internally - out of scope for this pass
- ProductBuyPanel: quantity stepper, wired to CartProvider.addItem() instead
  of its own ad-hoc fetch+token logic, toast on success
- Cart/CartItem types are a best-effort guess at an undocumented response
  shape (OpenAPI gives no field-level schema) - unverified against real data
  since store-items are still empty; read every field defensively

Store-items pages (new): /store-items (flat listing of purchasable variants,
always priced unlike /products) and /store-items/{id} (detail - no slug,
resolves the variant's productId and reuses the product's own gallery/
description/technical-info/comments/related-products, just with that
variant preselected).

Contact form: now shows a toast + inline success text and resets while
staying on screen, instead of swapping to a separate "thank you" panel.

New shared providers: ToastProvider (useToast) and CartProvider, both
mounted once in layout.tsx.

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

src/components/ContactForm.tsx

@@ -2,22 +2,28 @@
 
 import { useState } from "react";
 import { submitContactForm } from "@/lib/api";
+import { useToast } from "./providers/ToastProvider";
+import { CheckIcon } from "./icons";
 
 type Status = "idle" | "submitting" | "sent" | "error";
 
 // Posts straight to POST /tenants/moalem.shop/contact-submissions — a real,
-// documented endpoint, no bearer required.
+// documented endpoint, no bearer required. On success: a toast, inline
+// success text, and the form resets and stays put (not swapped for a
+// separate "thank you" panel) so another message can be sent right away.
 export default function ContactForm() {
   const [status, setStatus] = useState<Status>("idle");
+  const { showToast } = useToast();
 
   async function handleSubmit(e: React.FormEvent<HTMLFormElement>) {
     e.preventDefault();
-    const form = new FormData(e.currentTarget);
-    const name = String(form.get("name") || "").trim();
-    const title = String(form.get("title") || "").trim();
-    const text = String(form.get("text") || "").trim();
-    const email = String(form.get("email") || "").trim();
-    const cellNumber = String(form.get("cellNumber") || "").trim();
+    const form = e.currentTarget;
+    const data = new FormData(form);
+    const name = String(data.get("name") || "").trim();
+    const title = String(data.get("title") || "").trim();
+    const text = String(data.get("text") || "").trim();
+    const email = String(data.get("email") || "").trim();
+    const cellNumber = String(data.get("cellNumber") || "").trim();
     if (!name || !title || !text) return;
 
     setStatus("submitting");
@@ -29,33 +35,19 @@ export default function ContactForm() {
         email: email || undefined,
         cellNumber: cellNumber || undefined,
       });
+      form.reset();
       setStatus("sent");
-      e.currentTarget.reset();
+      showToast("پیام شما با موفقیت ارسال شد");
     } catch {
       setStatus("error");
     }
   }
 
-  if (status === "sent") {
-    return (
-      <div className="flex flex-col items-center gap-3 rounded-2xl border border-line bg-surface p-10 text-center">
-        <p className="text-[15px] font-bold text-ink">پیام شما با موفقیت ارسال شد.</p>
-        <p className="text-[13px] text-body">همکاران ما در اسرع وقت با شما تماس می‌گیرند.</p>
-        <button
-          onClick={() => setStatus("idle")}
-          className="mt-2 rounded-lg border border-line px-4 py-2 text-[13px] text-ink-soft transition hover:border-brand hover:text-brand"
-        >
-          ارسال پیام دیگر
-        </button>
-      </div>
-    );
-  }
-
   const input =
     "h-12 w-full rounded-xl border border-line bg-white px-4 text-sm outline-none transition focus:border-brand";
 
   return (
-    <form onSubmit={handleSubmit} className="space-y-4">
+    <form onSubmit={handleSubmit} onChange={() => status === "sent" && setStatus("idle")} className="space-y-4">
       <div className="grid grid-cols-1 gap-4 sm:grid-cols-2">
         <input name="name" required placeholder="نام و نام خانوادگی" className={input} />
         <input name="cellNumber" placeholder="شماره موبایل" inputMode="tel" className={input} />
@@ -75,6 +67,12 @@ export default function ContactForm() {
       {status === "error" && (
         <p className="text-[12.5px] text-brand">ارسال پیام ناموفق بود. لطفاً دوباره تلاش کنید.</p>
       )}
+      {status === "sent" && (
+        <p className="flex items-center gap-1.5 text-[12.5px] font-bold text-brand">
+          <CheckIcon className="size-4" />
+          پیام شما ارسال شد. همکاران ما در اسرع وقت با شما تماس می‌گیرند.
+        </p>
+      )}
 
       <button
         type="submit"