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>

lib/seo/dates.ts

@@ -0,0 +1,29 @@
+/**
+ * Formats a JS Date as an ISO 8601 string carrying its actual Europe/Berlin
+ * UTC offset (e.g. "2026-06-15T09:00:00+02:00" in summer,
+ * "...+01:00" in winter) — what schema.org's Event startDate/endDate
+ * expect. Uses Intl's timezone database rather than hardcoded +1/+2 math,
+ * so it's correct across the DST transition automatically.
+ */
+export function toBerlinOffsetISOString(date: Date): string {
+  const parts = new Intl.DateTimeFormat("en-US", {
+    timeZone: "Europe/Berlin",
+    year: "numeric",
+    month: "2-digit",
+    day: "2-digit",
+    hour: "2-digit",
+    minute: "2-digit",
+    second: "2-digit",
+    hourCycle: "h23",
+    timeZoneName: "shortOffset",
+  }).formatToParts(date);
+
+  const get = (type: string) => parts.find((p) => p.type === type)?.value ?? "00";
+  const tzName = parts.find((p) => p.type === "timeZoneName")?.value ?? "GMT+0";
+  const match = /GMT([+-])(\d+)(?::(\d+))?/.exec(tzName);
+  const sign = match?.[1] ?? "+";
+  const offsetHours = (match?.[2] ?? "0").padStart(2, "0");
+  const offsetMinutes = (match?.[3] ?? "0").padStart(2, "0");
+
+  return `${get("year")}-${get("month")}-${get("day")}T${get("hour")}:${get("minute")}:${get("second")}${sign}${offsetHours}:${offsetMinutes}`;
+}