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/[id]/page.tsx

@@ -1,6 +1,7 @@
 import type { Metadata } from 'next';
 import { notFound, permanentRedirect } from 'next/navigation';
 import EventDetailClient from './EventDetailClient';
+import type { EventSalesState } from '@/lib/api';
 
 const siteUrl = process.env.NEXT_PUBLIC_SITE_URL || 'https://spanglish.com.py';
 const apiUrl = process.env.NEXT_PUBLIC_API_URL || 'http://localhost:3001';
@@ -26,6 +27,7 @@ interface Event {
   availableSeats?: number;
   bookedCount?: number;
   presaleClosesAt?: string | null;
+  salesState?: EventSalesState;
   createdAt: string;
   updatedAt: string;
 }
@@ -114,19 +116,23 @@ function generateEventJsonLd(event: Event) {
       name: 'Spanglish',
       url: siteUrl,
     },
+    // The offer is always the online price; the door price is never published
+    // here. In the `door` state seats can still be bought (at the door), so it
+    // stays InStock and drops the pre-sale validThrough, which is in the past.
     offers: {
       '@type': 'Offer',
       price: event.price,
       priceCurrency: event.currency,
       availability:
+        event.salesState === 'sold_out' ||
         (typeof event.availableSeats === 'number'
           ? event.availableSeats
-          : Math.max(0, (event.capacity ?? 0) - (event.bookedCount ?? 0))) > 0
-        ? 'https://schema.org/InStock'
-        : 'https://schema.org/SoldOut',
+          : Math.max(0, (event.capacity ?? 0) - (event.bookedCount ?? 0))) <= 0
+        ? 'https://schema.org/SoldOut'
+        : 'https://schema.org/InStock',
       url: `${siteUrl}/events/${event.slug}`,
       validFrom: new Date().toISOString(),
-      ...(event.presaleClosesAt ? { validThrough: event.presaleClosesAt } : {}),
+      ...(event.presaleClosesAt && event.salesState !== 'door' ? { validThrough: event.presaleClosesAt } : {}),
     },
     image: event.bannerUrl
       ? (event.bannerUrl.startsWith('http') ? event.bannerUrl : `${siteUrl}${event.bannerUrl}`)