Add standalone registration page; fix 2 merkliste bugs; honor login redirect

New /konto/registrieren (+ RegisterForm.tsx) — until now an account
could only be created inline during checkout, which stopped making
sense the moment the Wishlist gave accounts a non-purchase use case.
LoginForm now also honors ?redirect= (previously ignored, always
landing on /konto/bestellungen regardless of where the login was
triggered from, e.g. WishlistButton's login-gate) and links to the
new registration page instead of implying "only via checkout".

Fixed: removing an item from the wishlist didn't disappear from
/konto/merkliste — that page was a Server Component with a fixed
render, not reactive to the client-side toggle. New MerklisteGrid.tsx
(Client Component) uses useWishlist()'s live state as the actual
source of truth for which products are still shown.

Fixed: AddToCartInlineButton looked broken on that same page —
`className="w-full"` was passed to it, but its `className` prop
*replaces* the whole default styling (`?? default`, not a merge),
throwing away all the button's actual styling. Its default is
already `w-full`; no override needed.

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

app/konto/login/components/LoginForm.tsx

@@ -1,7 +1,7 @@
 "use client";
 
 import { useState } from "react";
-import { useRouter } from "next/navigation";
+import { useRouter, useSearchParams } from "next/navigation";
 import Link from "next/link";
 import { Reveal } from "../../../components/Reveal";
 import { mergeServerCartIntoLocal } from "../../../lib/cart";
@@ -9,6 +9,12 @@ import { dispatchAuthChanged } from "../../../lib/auth";
 
 export function LoginForm() {
   const router = useRouter();
+  const searchParams = useSearchParams();
+  // WishlistButton (and anything else login-gated) sends the shopper back
+  // here with ?redirect=<where they were>, e.g. a product page they
+  // wanted to heart — previously ignored, always landing on
+  // /konto/bestellungen regardless of where the login was triggered from.
+  const redirectTo = searchParams.get("redirect") || "/konto/bestellungen";
   const [email, setEmail] = useState("");
   const [password, setPassword] = useState("");
   const [error, setError] = useState<string | null>(null);
@@ -32,7 +38,7 @@ export function LoginForm() {
       }
       await mergeServerCartIntoLocal();
       dispatchAuthChanged();
-      router.push("/konto/bestellungen");
+      router.push(redirectTo);
       router.refresh();
     } catch {
       setError("Login ist gerade nicht möglich.");
@@ -81,11 +87,14 @@ export function LoginForm() {
         Passwort vergessen?
       </Link>
       <p className="text-body-sm text-text-muted">
-        Noch kein Konto? Einfach beim{" "}
-        <Link href="/checkout" className="underline hover:text-brand transition-colors">
-          nächsten Einkauf
-        </Link>{" "}
-        anlegen.
+        Noch kein Konto?{" "}
+        <Link
+          href={`/konto/registrieren${redirectTo !== "/konto/bestellungen" ? `?redirect=${encodeURIComponent(redirectTo)}` : ""}`}
+          className="underline hover:text-brand transition-colors"
+        >
+          Jetzt anlegen
+        </Link>
+        .
       </p>
     </Reveal>
   );

app/konto/login/page.tsx

@@ -1,4 +1,5 @@
 import type { Metadata } from "next";
+import { Suspense } from "react";
 import { LoginForm } from "./components/LoginForm";
 import { Footer } from "../../components/Footer";
 
@@ -16,7 +17,12 @@ export default function KontoLoginPage() {
   return (
     <>
       <main className="flex flex-col flex-1 bg-bg-base">
-        <LoginForm />
+        {/* Suspense required — LoginForm uses useSearchParams() (?redirect=,
+            e.g. from WishlistButton's login-gate) which opts any consumer
+            into client-side rendering unless wrapped. */}
+        <Suspense fallback={null}>
+          <LoginForm />
+        </Suspense>
       </main>
       <Footer />
     </>

app/konto/merkliste/components/MerklisteGrid.tsx

@@ -0,0 +1,88 @@
+"use client";
+
+import Image from "next/image";
+import { RevealGroup, RevealItem } from "../../../components/Reveal";
+import { formatPrice, discountPercent } from "../../../lib/format";
+import { AddToCartInlineButton } from "../../../components/AddToCartInlineButton";
+import { WishlistButton } from "../../../components/WishlistButton";
+import { useWishlist } from "../../../lib/useWishlist";
+import { effectiveTaxRate } from "../../../lib/cartTotals";
+import type { Product } from "../../../lib/payload";
+
+// Client Component so removing an item (WishlistButton toggling it off)
+// disappears from this grid immediately — the server-rendered initial
+// list alone doesn't react to that client-side toggle at all (the parent
+// page.tsx is a Server Component, its render is fixed at request time).
+// useWishlist()'s live `items` is the actual source of truth for which
+// products are still wishlisted; `initialProducts` only supplies the
+// display data (name/image/price) for whatever numericIds are currently
+// wishlisted, since the wishlist itself only stores product ids.
+export function MerklisteGrid({
+  initialProducts,
+  defaultTaxRate,
+  kleinunternehmer,
+}: {
+  initialProducts: Product[];
+  defaultTaxRate: number;
+  kleinunternehmer: boolean;
+}) {
+  const { items } = useWishlist();
+  const wishlistedIds = new Set(items.map((i) => i.productId));
+  // Preserve the wishlist's own order (most-recently-added-first, via
+  // `items`) rather than initialProducts' own order.
+  const productsByNumericId = new Map(initialProducts.map((p) => [p.numericId, p]));
+  const visibleProducts = items.map((i) => productsByNumericId.get(i.productId)).filter((p): p is Product => Boolean(p));
+
+  if (visibleProducts.length === 0) {
+    return <p className="text-body text-text-muted">Du hast noch keine Produkte gemerkt.</p>;
+  }
+
+  return (
+    <RevealGroup className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 gap-6 w-full">
+      {visibleProducts.map((product) => {
+        const discount = discountPercent(product.price, product.compareAtPrice);
+        const taxRate = effectiveTaxRate(product, defaultTaxRate);
+        const fullyOutOfStock = product.variants.length > 0 ? product.variants.every((v) => v.outOfStock) : product.outOfStock;
+        return (
+          <RevealItem key={product.id} className="bg-bg-base border border-border rounded-md overflow-hidden flex flex-col h-full">
+            <div className="relative w-full aspect-[276/210] overflow-hidden">
+              <Image
+                src={product.image}
+                alt={product.name}
+                fill
+                sizes="(min-width: 1024px) 33vw, (min-width: 640px) 50vw, 100vw"
+                className={`object-cover ${fullyOutOfStock ? "opacity-60" : ""}`}
+              />
+              {fullyOutOfStock && (
+                <span className="absolute top-3 left-3 rounded-full bg-text-muted px-2.5 py-1 text-label font-bold text-bg-base">
+                  Ausverkauft
+                </span>
+              )}
+              <WishlistButton productId={product.numericId} className="absolute top-3 right-3" />
+            </div>
+            <div className="flex flex-col gap-4 items-start px-5 pb-5 pt-4 w-full flex-1">
+              <p className="font-semibold text-h4 text-text-primary w-full" style={{ fontFamily: "var(--font-lora)" }}>
+                {product.name}
+              </p>
+              <div className="flex flex-col gap-1 items-start">
+                <p className="flex items-baseline gap-1.5">
+                  {discount !== null && (
+                    <span className="text-label text-text-muted line-through">{formatPrice(product.compareAtPrice!)}</span>
+                  )}
+                  <span className="font-bold text-h4 text-text-primary">{formatPrice(product.price)}</span>
+                  {!kleinunternehmer && <span className="text-label text-text-muted">inkl. {taxRate}% MwSt.</span>}
+                </p>
+              </div>
+              {/* No className override — AddToCartInlineButton's `className`
+                  prop REPLACES its whole default styling (`?? defaultClass`,
+                  not a merge), so passing just "w-full" here previously threw
+                  away all the button's actual styling. Its default is
+                  already `w-full`. */}
+              <AddToCartInlineButton id={product.id} outOfStock={product.outOfStock} maxQty={product.maxQty} variants={product.variants} />
+            </div>
+          </RevealItem>
+        );
+      })}
+    </RevealGroup>
+  );
+}

app/konto/merkliste/page.tsx

@@ -1,15 +1,11 @@
 import type { Metadata } from "next";
 import { redirect, notFound } from "next/navigation";
 import Link from "next/link";
-import Image from "next/image";
-import { Reveal, RevealGroup, RevealItem } from "../../components/Reveal";
+import { Reveal } from "../../components/Reveal";
 import { Footer } from "../../components/Footer";
-import { formatPrice, discountPercent } from "../../lib/format";
 import { getSessionCustomer, getWishlist } from "../../lib/customerAuth";
 import { getProductsByIds, getWishlistEnabled, getDefaultTaxRatePercent, getKleinunternehmer } from "../../lib/payload";
-import { effectiveTaxRate } from "../../lib/cartTotals";
-import { AddToCartInlineButton } from "../../components/AddToCartInlineButton";
-import { WishlistButton } from "../../components/WishlistButton";
+import { MerklisteGrid } from "./components/MerklisteGrid";
 
 // robots: noindex — account area, same reasoning as /konto/bestellungen.
 export const metadata: Metadata = {
@@ -37,13 +33,7 @@ export default async function KontoMerklistePage() {
     getDefaultTaxRatePercent(),
     getKleinunternehmer(),
   ]);
-  const products = await getProductsByIds(wishlistItems.map((i) => i.productId));
-  // Preserve the wishlist's own most-recently-added-first order rather
-  // than whatever order the products query happens to return in.
-  const productsByNumericId = new Map(products.map((p) => [p.numericId, p]));
-  const orderedProducts = wishlistItems
-    .map((item) => productsByNumericId.get(item.productId))
-    .filter((p): p is NonNullable<typeof p> => Boolean(p));
+  const initialProducts = await getProductsByIds(wishlistItems.map((i) => i.productId));
 
   return (
     <>
@@ -53,60 +43,7 @@ export default async function KontoMerklistePage() {
             Meine Merkliste
           </p>
 
-          {orderedProducts.length === 0 ? (
-            <p className="text-body text-text-muted">Du hast noch keine Produkte gemerkt.</p>
-          ) : (
-            <RevealGroup className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 gap-6 w-full">
-              {orderedProducts.map((product) => {
-                const discount = discountPercent(product.price, product.compareAtPrice);
-                const taxRate = effectiveTaxRate(product, defaultTaxRate);
-                const fullyOutOfStock = product.variants.length > 0 ? product.variants.every((v) => v.outOfStock) : product.outOfStock;
-                return (
-                  <RevealItem
-                    key={product.id}
-                    className="bg-bg-base border border-border rounded-md overflow-hidden flex flex-col h-full"
-                  >
-                    <div className="relative w-full aspect-[276/210] overflow-hidden">
-                      <Image
-                        src={product.image}
-                        alt={product.name}
-                        fill
-                        sizes="(min-width: 1024px) 33vw, (min-width: 640px) 50vw, 100vw"
-                        className={`object-cover ${fullyOutOfStock ? "opacity-60" : ""}`}
-                      />
-                      {fullyOutOfStock && (
-                        <span className="absolute top-3 left-3 rounded-full bg-text-muted px-2.5 py-1 text-label font-bold text-bg-base">
-                          Ausverkauft
-                        </span>
-                      )}
-                      <WishlistButton productId={product.numericId} className="absolute top-3 right-3" />
-                    </div>
-                    <div className="flex flex-col gap-4 items-start px-5 pb-5 pt-4 w-full flex-1">
-                      <p className="font-semibold text-h4 text-text-primary w-full" style={{ fontFamily: "var(--font-lora)" }}>
-                        {product.name}
-                      </p>
-                      <div className="flex flex-col gap-1 items-start">
-                        <p className="flex items-baseline gap-1.5">
-                          {discount !== null && (
-                            <span className="text-label text-text-muted line-through">{formatPrice(product.compareAtPrice!)}</span>
-                          )}
-                          <span className="font-bold text-h4 text-text-primary">{formatPrice(product.price)}</span>
-                          {!kleinunternehmer && <span className="text-label text-text-muted">inkl. {taxRate}% MwSt.</span>}
-                        </p>
-                      </div>
-                      <AddToCartInlineButton
-                        id={product.id}
-                        outOfStock={product.outOfStock}
-                        maxQty={product.maxQty}
-                        variants={product.variants}
-                        className="w-full"
-                      />
-                    </div>
-                  </RevealItem>
-                );
-              })}
-            </RevealGroup>
-          )}
+          <MerklisteGrid initialProducts={initialProducts} defaultTaxRate={defaultTaxRate} kleinunternehmer={kleinunternehmer} />
 
           <div className="flex gap-6 self-center sm:self-start">
             <Link href="/konto/bestellungen" className="underline text-body-sm text-text-primary hover:text-brand transition-colors">

app/konto/registrieren/components/RegisterForm.tsx

@@ -0,0 +1,127 @@
+"use client";
+
+import { useState } from "react";
+import { useRouter, useSearchParams } from "next/navigation";
+import Link from "next/link";
+import { Reveal } from "../../../components/Reveal";
+import { mergeServerCartIntoLocal } from "../../../lib/cart";
+import { dispatchAuthChanged } from "../../../lib/auth";
+
+// Standalone registration, independent of checkout — until the Wishlist
+// shipped, the only way to get a customer account was the inline
+// registration step inside checkout (see api/checkout/route.ts), which
+// made sense when an account only ever existed to hold an order. That
+// stopped being true the moment a shopper could want an account just to
+// save products to a Wishlist without buying anything yet.
+export function RegisterForm() {
+  const router = useRouter();
+  const searchParams = useSearchParams();
+  const redirectTo = searchParams.get("redirect") || "/konto/bestellungen";
+  const [firstName, setFirstName] = useState("");
+  const [lastName, setLastName] = useState("");
+  const [email, setEmail] = useState("");
+  const [password, setPassword] = useState("");
+  const [error, setError] = useState<string | null>(null);
+  const [loading, setLoading] = useState(false);
+
+  async function handleSubmit(e: React.FormEvent<HTMLFormElement>) {
+    e.preventDefault();
+    setLoading(true);
+    setError(null);
+    try {
+      const res = await fetch("/api/account/register", {
+        method: "POST",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ firstName, lastName, email, password }),
+      });
+      const data = await res.json();
+      if (!data.ok) {
+        setError(data.reason || "Registrierung fehlgeschlagen.");
+        setLoading(false);
+        return;
+      }
+      await mergeServerCartIntoLocal();
+      dispatchAuthChanged();
+      router.push(redirectTo);
+      router.refresh();
+    } catch {
+      setError("Registrierung ist gerade nicht möglich.");
+      setLoading(false);
+    }
+  }
+
+  return (
+    <Reveal className="flex flex-col gap-6 items-start pt-10 pb-20 px-[var(--layout-padding-x)] w-full max-w-[26rem] mx-auto">
+      <p className="font-semibold text-h-feature text-text-primary" style={{ fontFamily: "var(--font-lora)" }}>
+        Konto anlegen
+      </p>
+      <form onSubmit={handleSubmit} className="flex flex-col gap-4 items-start w-full">
+        <div className="flex gap-4 w-full">
+          <label className="flex flex-col gap-2 items-start w-full">
+            <span className="text-label text-text-muted">Vorname</span>
+            <input
+              type="text"
+              required
+              autoComplete="given-name"
+              value={firstName}
+              onChange={(e) => setFirstName(e.target.value)}
+              className="w-full border border-border rounded-sm px-4 py-3 text-body-sm text-text-primary outline-none focus:border-brand transition-colors"
+            />
+          </label>
+          <label className="flex flex-col gap-2 items-start w-full">
+            <span className="text-label text-text-muted">Nachname</span>
+            <input
+              type="text"
+              required
+              autoComplete="family-name"
+              value={lastName}
+              onChange={(e) => setLastName(e.target.value)}
+              className="w-full border border-border rounded-sm px-4 py-3 text-body-sm text-text-primary outline-none focus:border-brand transition-colors"
+            />
+          </label>
+        </div>
+        <label className="flex flex-col gap-2 items-start w-full">
+          <span className="text-label text-text-muted">E-Mail-Adresse</span>
+          <input
+            type="email"
+            required
+            autoComplete="email"
+            value={email}
+            onChange={(e) => setEmail(e.target.value)}
+            className="w-full border border-border rounded-sm px-4 py-3 text-body-sm text-text-primary outline-none focus:border-brand transition-colors"
+          />
+        </label>
+        <label className="flex flex-col gap-2 items-start w-full">
+          <span className="text-label text-text-muted">Passwort</span>
+          <input
+            type="password"
+            required
+            minLength={8}
+            autoComplete="new-password"
+            value={password}
+            onChange={(e) => setPassword(e.target.value)}
+            className="w-full border border-border rounded-sm px-4 py-3 text-body-sm text-text-primary outline-none focus:border-brand transition-colors"
+          />
+        </label>
+        {error && <p className="text-label text-red-600">{error}</p>}
+        <button
+          type="submit"
+          disabled={loading}
+          className={`w-full flex items-center justify-center py-4 rounded-sm bg-brand hover:bg-brand-hover active:scale-[0.97] transition-all font-bold text-body text-text-primary ${loading ? "opacity-70 pointer-events-none" : ""}`}
+        >
+          {loading ? "Einen Moment…" : "Konto anlegen"}
+        </button>
+      </form>
+      <p className="text-body-sm text-text-muted">
+        Schon ein Konto?{" "}
+        <Link
+          href={`/konto/login${redirectTo !== "/konto/bestellungen" ? `?redirect=${encodeURIComponent(redirectTo)}` : ""}`}
+          className="underline hover:text-brand transition-colors"
+        >
+          Einloggen
+        </Link>
+        .
+      </p>
+    </Reveal>
+  );
+}

app/konto/registrieren/page.tsx

@@ -0,0 +1,29 @@
+import type { Metadata } from "next";
+import { Suspense } from "react";
+import { RegisterForm } from "./components/RegisterForm";
+import { Footer } from "../../components/Footer";
+
+// robots: noindex — account area, same reasoning as /konto/login.
+export const metadata: Metadata = {
+  title: "Konto anlegen",
+  description: "Lege ein Konto bei einfach produktiv an.",
+  robots: {
+    index: false,
+    follow: true,
+  },
+};
+
+export default function KontoRegistrierenPage() {
+  return (
+    <>
+      <main className="flex flex-col flex-1 bg-bg-base">
+        {/* Suspense required — RegisterForm uses useSearchParams() (?redirect=),
+            same reasoning as /konto/login's own page. */}
+        <Suspense fallback={null}>
+          <RegisterForm />
+        </Suspense>
+      </main>
+      <Footer />
+    </>
+  );
+}