Add password reset, order confirmation email with editable templates, and fix missing account entry points

Password reset uses Payload's built-in forgot/reset-password flow,
customized to link to this app instead of the Payload admin. Order
confirmation email and the password-reset email's wording both come from
a new Payload email-templates collection, editable without a deploy and
previewable via Live Preview at /email-preview/[type] (same mechanism as
Posts/LegalPages/Testimonials, sample data instead of a real document).

Also: order numbers get a random suffix (prevents guessing, motivated by
a considered-and-deferred guest order-lookup feature); the discount code
field only shows in the cart when a code is actually active (codes now
apply via a ?code= link instead of manual entry); and three navigation
gaps found while testing — no reachable login link with an empty cart, no
logout link anywhere, no way back from profile to order history.

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

app/cart/page.tsx

@@ -1,4 +1,5 @@
 import type { Metadata } from "next";
+import { Suspense } from "react";
 import { CartContent } from "./components/CartContent";
 import { RelatedProducts } from "./components/RelatedProducts";
 import { TrustRow } from "../components/TrustRow";
@@ -38,12 +39,20 @@ export default async function CartPage() {
   return (
     <>
       <main className="flex flex-col flex-1 bg-bg-base">
-        <CartContent
-          trustBadges={trustBadges}
-          shippingCost={defaultShipping?.price ?? 0}
-          freeShippingThreshold={freeShippingThreshold}
-          shippingSettings={shipping}
-        />
+        {/* Suspense required — CartContent uses useSearchParams() (?code=
+            auto-apply, see its own comment) which opts any consumer into
+            client-side rendering unless wrapped. fallback={null}: the cart
+            itself is entirely client-rendered from localStorage anyway
+            (see CartContent's own productsLoading handling), so there's no
+            meaningful server-rendered content this would flash away from. */}
+        <Suspense fallback={null}>
+          <CartContent
+            trustBadges={trustBadges}
+            shippingCost={defaultShipping?.price ?? 0}
+            freeShippingThreshold={freeShippingThreshold}
+            shippingSettings={shipping}
+          />
+        </Suspense>
         <RelatedProducts />
         <TrustRow />
       </main>