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/admin/events/_components/EventFormModal.tsx

@@ -24,6 +24,7 @@ interface EventFormData {
   endDatetime: string;
   location: string;
   locationUrl: string;
+  series: string;
   price: number;
   // Kept as the raw input so "empty" (not set -> falls back to price) stays
   // distinguishable from 0 (a free walk-in).
@@ -49,7 +50,7 @@ const FALLBACK_PRESALE_DEFAULTS: PresaleDefaults = { enabled: true, minutesBefor
 const EMPTY_FORM: EventFormData = {
   title: '', titleEs: '', slug: '', description: '', descriptionEs: '',
   shortDescription: '', shortDescriptionEs: '',
-  startDatetime: '', endDatetime: '', location: '', locationUrl: '',
+  startDatetime: '', endDatetime: '', location: '', locationUrl: '', series: '',
   price: 0, walkInPrice: '', currency: 'PYG', capacity: 50, status: 'draft',
   bannerUrl: '', externalBookingEnabled: false, externalBookingUrl: '',
   presaleClosureEnabled: FALLBACK_PRESALE_DEFAULTS.enabled,
@@ -147,7 +148,7 @@ export default function EventFormModal({
         shortDescription: event.shortDescription || '', shortDescriptionEs: event.shortDescriptionEs || '',
         startDatetime: isoToLocalDatetime(event.startDatetime),
         endDatetime: event.endDatetime ? isoToLocalDatetime(event.endDatetime) : '',
-        location: event.location, locationUrl: event.locationUrl || '',
+        location: event.location, locationUrl: event.locationUrl || '', series: event.series || '',
         price: event.price, currency: event.currency, capacity: event.capacity,
         walkInPrice: event.walkInPrice == null ? '' : String(event.walkInPrice),
         status: event.status, bannerUrl: event.bannerUrl || '',
@@ -232,6 +233,7 @@ export default function EventFormModal({
         startDatetime: formData.startDatetime,
         endDatetime: formData.endDatetime || undefined,
         location: formData.location, locationUrl: formData.locationUrl || undefined,
+        series: formData.series.trim() || null,
         price: formData.price, currency: formData.currency, capacity: formData.capacity,
         // Empty means "not set" and must be saved as null, never 0
         walkInPrice: formData.walkInPrice.trim() === '' ? null : Number(formData.walkInPrice),
@@ -360,6 +362,11 @@ export default function EventFormModal({
             onChange={(e) => setFormData({ ...formData, location: e.target.value })} required />
           <Input label="Location URL (Google Maps)" type="url" value={formData.locationUrl}
             onChange={(e) => setFormData({ ...formData, locationUrl: e.target.value })} />
+          <div>
+            <Input label={t('admin.eventForm.series')} value={formData.series} maxLength={100} placeholder="Morning Club"
+              onChange={(e) => setFormData({ ...formData, series: e.target.value })} />
+            <p className="text-xs text-gray-500 mt-1">{t('admin.eventForm.seriesHint')}</p>
+          </div>
 
           <div>
             <div className="grid grid-cols-1 md:grid-cols-3 gap-4">