feat: add website social link, fix herkunft origin display, GUI backup schedule, and format-based batch numbering

- SiteSettings gains websiteUrl (e.g. online shop link) alongside the
  existing social links, editable in Verwaltung > Automatisierung.
- /herkunft/[lot] now shows the apiary's Standort instead of its internal
  Name (so multiple apiaries at one location read as one origin), adds
  small icons per social link, and surfaces previously-fetched-but-unused
  data (Honigsorte, Abfülldatum, stat cards) to make the page a richer
  customer-facing info page.
- Backup schedule (path/cron/retention) is now also configurable via the
  GUI (Verwaltung > Backup), stored in a new BackupSettings singleton;
  an env var always wins over the GUI value per field, and the scheduler
  reloads its cron job live when GUI settings change.
- New Automatisierung rules let an admin define a format (e.g.
  "WH-{YYYY}-{SEQ:4}") that auto-generates HoneyBatch.batchNumber and
  BottlingBatch.lotNumber on creation, with an atomic per-rule sequence
  counter and a manual reset. Manual entry still works when the rule is
  inactive.

ApiCore-Backend/src/automation/number-format.ts

@@ -0,0 +1,24 @@
+// Placeholders: {YYYY} 4-digit year, {YY} 2-digit year, {MM} month (01-12),
+// {DD} day (01-31), {SEQ} running sequence unpadded, {SEQ:N} sequence
+// zero-padded to N digits. Example matching the lastenheft's own sample
+// ("WH-2026-0001"): format "WH-{YYYY}-{SEQ:4}".
+export function formatGeneratedNumber(
+  format: string,
+  sequence: number,
+  date: Date,
+): string {
+  const yyyy = String(date.getFullYear());
+  const yy = yyyy.slice(-2);
+  const mm = String(date.getMonth() + 1).padStart(2, '0');
+  const dd = String(date.getDate()).padStart(2, '0');
+
+  return format
+    .replace(/\{YYYY\}/g, yyyy)
+    .replace(/\{YY\}/g, yy)
+    .replace(/\{MM\}/g, mm)
+    .replace(/\{DD\}/g, dd)
+    .replace(/\{SEQ:(\d+)\}/g, (_match, width: string) =>
+      String(sequence).padStart(Number(width), '0'),
+    )
+    .replace(/\{SEQ\}/g, String(sequence));
+}