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/calendar/timezone.ts

@@ -0,0 +1,57 @@
+const BERLIN_TZ = "Europe/Berlin";
+
+/**
+ * Converts a JS Date (a UTC instant) into its Europe/Berlin wall-clock
+ * representation for iCalendar's local `TZID` date-time form
+ * (`DTSTART;TZID=Europe/Berlin:YYYYMMDDTHHMMSS`). Uses the ICU timezone
+ * database via Intl rather than manual UTC+1/+2 arithmetic, so daylight
+ * saving transitions are always handled correctly — no naive UTC offset
+ * math that would drift by an hour half the year.
+ */
+export function toBerlinICSDateTime(date: Date): string {
+  const parts = new Intl.DateTimeFormat("en-US", {
+    timeZone: BERLIN_TZ,
+    year: "numeric",
+    month: "2-digit",
+    day: "2-digit",
+    hour: "2-digit",
+    minute: "2-digit",
+    second: "2-digit",
+    hourCycle: "h23",
+  }).formatToParts(date);
+
+  const get = (type: string) => parts.find((p) => p.type === type)?.value ?? "00";
+  return `${get("year")}${get("month")}${get("day")}T${get("hour")}${get("minute")}${get("second")}`;
+}
+
+/** UTC timestamp form (`YYYYMMDDTHHMMSSZ`) — used only for DTSTAMP, which marks generation time, not a local event time. */
+export function toUTCICSStamp(date: Date): string {
+  return date.toISOString().replace(/[-:]/g, "").split(".")[0] + "Z";
+}
+
+/**
+ * Standard IANA Europe/Berlin VTIMEZONE block (the same one commonly
+ * embedded by calendar exporters): CEST from the last Sunday in March,
+ * CET from the last Sunday in October — the actual EU DST rule, not an
+ * approximation.
+ */
+export const BERLIN_VTIMEZONE_LINES = [
+  "BEGIN:VTIMEZONE",
+  "TZID:Europe/Berlin",
+  "X-LIC-LOCATION:Europe/Berlin",
+  "BEGIN:DAYLIGHT",
+  "TZOFFSETFROM:+0100",
+  "TZOFFSETTO:+0200",
+  "TZNAME:CEST",
+  "DTSTART:19700329T020000",
+  "RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU",
+  "END:DAYLIGHT",
+  "BEGIN:STANDARD",
+  "TZOFFSETFROM:+0200",
+  "TZOFFSETTO:+0100",
+  "TZNAME:CET",
+  "DTSTART:19701025T030000",
+  "RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU",
+  "END:STANDARD",
+  "END:VTIMEZONE",
+];