Add email verification, personal calendar feed, and full SEO implementation

- Customer accounts now require email verification (hashed, single-use,
  time-limited tokens) before they can request/confirm bookings, with
  resend flows on login/account/booking widget and rate limiting.
- Admins get a private, rotatable iCalendar (ICS) subscription feed of
  their confirmed bookings and public events, timezone-correct for
  Europe/Berlin including DST, never exposing meeting passwords.
- Adds a full SEO layer: per-page canonical/OG/Twitter metadata with
  CMS-editable overrides and content-derived fallbacks, a dynamic
  sitemap.xml and robots.txt driven by real published content, JSON-LD
  (Organization/LocalBusiness, WebSite, WebPage, BreadcrumbList, Service,
  Event, BlogPosting) that never fabricates data, and a CMS-managed
  redirect table for changed slugs.
- Global ANOUMA-naming audit: the brand name is never used to label
  personal account/calendar areas anywhere in the app, CMS, or emails.

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

components/auth/ResendVerificationButton.tsx

@@ -0,0 +1,134 @@
+"use client";
+
+import { useState, type FormEvent } from "react";
+
+const fieldClass =
+  "w-full rounded-2xl border border-anouma-taupe/30 bg-white px-4 py-2.5 text-sm text-anouma-plum placeholder:text-anouma-plum/50 focus:border-anouma-mauve-dark focus:outline-none";
+
+async function callResend(email?: string): Promise<{ ok: boolean; error?: string }> {
+  try {
+    const res = await fetch("/api/auth/resend-verification", {
+      method: "POST",
+      credentials: "include",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify(email ? { email } : {}),
+    });
+    const data = await res.json().catch(() => ({}));
+    if (!res.ok) return { ok: false, error: data.error || "Die Bestätigungs-E-Mail konnte nicht gesendet werden." };
+    return { ok: true };
+  } catch {
+    return { ok: false, error: "Verbindung fehlgeschlagen." };
+  }
+}
+
+const GENERIC_SENT_MESSAGE =
+  "Falls das Konto noch nicht bestätigt ist, wurde eine neue Bestätigungs-E-Mail gesendet.";
+
+/**
+ * variant "session": a single button that resends for the currently logged-in
+ * customer (used in /konto and the booking widget, where a session already
+ * exists).
+ *
+ * variant "email-prompt": a toggle link that reveals an email field first
+ * (used on /login, where the visitor may not be authenticated yet).
+ */
+export function ResendVerificationButton({
+  variant,
+  triggerLabel = "E-Mail noch nicht bestätigt?",
+  className,
+}: {
+  variant: "session" | "email-prompt";
+  triggerLabel?: string;
+  className?: string;
+}) {
+  const [open, setOpen] = useState(false);
+  const [status, setStatus] = useState<"idle" | "sending" | "sent" | "error">("idle");
+  const [error, setError] = useState<string | null>(null);
+
+  async function resendForSession() {
+    setStatus("sending");
+    const result = await callResend();
+    if (result.ok) {
+      setStatus("sent");
+    } else {
+      setStatus("error");
+      setError(result.error ?? null);
+    }
+  }
+
+  async function handleEmailSubmit(e: FormEvent<HTMLFormElement>) {
+    e.preventDefault();
+    setStatus("sending");
+    setError(null);
+    const email = String(new FormData(e.currentTarget).get("email") ?? "");
+    const result = await callResend(email);
+    if (result.ok) {
+      setStatus("sent");
+    } else {
+      setStatus("error");
+      setError(result.error ?? null);
+    }
+  }
+
+  if (variant === "session") {
+    return (
+      <div className={className}>
+        {status === "sent" ? (
+          <p className="text-sm text-anouma-olive">{GENERIC_SENT_MESSAGE}</p>
+        ) : (
+          <button
+            type="button"
+            onClick={resendForSession}
+            disabled={status === "sending"}
+            className="text-sm font-medium text-anouma-mauve-dark underline underline-offset-4 disabled:opacity-60"
+          >
+            {status === "sending" ? "Wird gesendet …" : "Bestätigungs-E-Mail erneut senden"}
+          </button>
+        )}
+        {status === "error" && error && (
+          <p role="alert" className="mt-1 text-sm text-red-700">
+            {error}
+          </p>
+        )}
+      </div>
+    );
+  }
+
+  return (
+    <div className={className}>
+      {!open ? (
+        <button
+          type="button"
+          onClick={() => setOpen(true)}
+          className="text-sm font-medium text-anouma-mauve-dark underline underline-offset-4"
+        >
+          {triggerLabel}
+        </button>
+      ) : status === "sent" ? (
+        <p className="text-sm text-anouma-olive">{GENERIC_SENT_MESSAGE}</p>
+      ) : (
+        <form onSubmit={handleEmailSubmit} className="mt-2 flex flex-wrap items-start gap-2">
+          <input
+            type="email"
+            name="email"
+            required
+            placeholder="Deine E-Mail-Adresse"
+            className={`${fieldClass} max-w-xs flex-1`}
+          />
+          <button
+            type="submit"
+            disabled={status === "sending"}
+            className="rounded-full bg-anouma-mauve-dark px-5 py-2.5 text-sm font-medium text-white hover:bg-anouma-plum disabled:opacity-60"
+          >
+            {status === "sending" ? "Wird gesendet …" : "Bestätigungs-E-Mail erneut senden"}
+          </button>
+        </form>
+      )}
+      {status === "error" && error && (
+        <p role="alert" className="mt-1 text-sm text-red-700">
+          {error}
+        </p>
+      )}
+    </div>
+  );
+}