Add per-event finance, event team permissions and public door sales state.

Event finance
- Finance tab on the event page: P&L summary with a revenue-to-result
  waterfall, costs and other income in one ledger, and the partner split
  with payouts. Lifecycle stepper (Selling, Adding costs, Ready to close,
  Finalized) with what is left to do; closing the books goes through a
  checklist dialog that freezes the numbers.
- Expense modal shows only the fields each calculation type needs, a live
  preview with the event's real counts, and a category suggested from the
  description. Date inputs follow the UI language.
- Global Finance page: profit per event with outliers clipped and labelled,
  and a "Ready to close" list of past events whose books are still open.
- Calculation service (integer PYG, basis points) with pinned regression
  scenarios; PYG formatting centralised in lib/money with locale-aware
  separators.

Event team permissions
- Per-event members with role presets and requireEventPermission; the
  header stat "Confirmed" is relabelled "Not checked in yet", which is
  what it counts.

Public sales state
- One sales state (online, door, sold out, ended, external, cancelled) for
  the event page, listings and JSON-LD, with the door price and tenders
  shown only while people can still pay at the door.

Frontend unit tests run with vitest (npm test in frontend/).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/src/app/(public)/events/EventsClient.tsx

@@ -18,11 +18,14 @@ export default function EventsClient({ initialEvents }: { initialEvents: Event[]
   const [filter, setFilter] = useState<'upcoming' | 'past'>('upcoming');
 
   const now = new Date();
+  // An event that has started but still sells at the door stays under Upcoming.
+  const isUpcoming = (e: Event) =>
+    new Date(e.startDatetime) >= now || e.salesState === 'door';
   const upcomingEvents = initialEvents.filter(e =>
-    e.status === 'published' && new Date(e.startDatetime) >= now
+    e.status === 'published' && isUpcoming(e)
   );
   const pastEvents = initialEvents.filter(e =>
-    e.status === 'completed' || (e.status === 'published' && new Date(e.startDatetime) < now)
+    e.status === 'completed' || (e.status === 'published' && !isUpcoming(e))
   );
 
   const displayedEvents = filter === 'upcoming' ? upcomingEvents : pastEvents;
@@ -34,9 +37,16 @@ export default function EventsClient({ initialEvents }: { initialEvents: Event[]
     if (event.status === 'cancelled') {
       return <span className="badge badge-danger">{t('events.details.cancelled')}</span>;
     }
-    if (event.availableSeats === 0) {
+    if (event.salesState === 'sold_out' || event.availableSeats === 0) {
       return <span className="badge badge-warning">{t('events.details.soldOut')}</span>;
     }
+    if (event.salesState === 'door') {
+      return (
+        <span className="badge bg-primary-yellow/20 text-primary-dark whitespace-nowrap">
+          {t('events.door.badge')}
+        </span>
+      );
+    }
     return null;
   };