feat(orders): reopen cancelled orders only after confirmation; accurate sales

Cancelled orders:
- Moving an order out of STORNIERT is possible again, but only after a
  warning is confirmed in the status form (OrderStatusForm); without
  the confirmation the server changes nothing.
- Reopening books the counter-entry to the cancellation: goods that the
  cancellation restocked are deducted again (atomically, only if enough
  stock is left, otherwise the order stays cancelled). A later second
  cancellation therefore restocks +1 again instead of leaving +2.
- The warning states that no new payment is collected.

Dashboard figures:
- One definition of a counted sale (lib/sales.ts): not unpaid (NEU),
  not cancelled, no refunded return. Used for revenue today/month, sold
  glasses, average cart, top products/categories, revenue trend and
  repeat customers.
- "Verkaufte Gläser" previously summed every order item, including
  cancelled orders and refunded returns.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

src/app/admin/page.tsx

@@ -1,6 +1,7 @@
 import Link from "next/link";
 import { ApiCoreSyncPanel, ApiCoreSyncResult } from "@/components/apicore-sync-panel";
 import { prisma } from "@/lib/prisma";
+import { COUNTED_SALE_WHERE } from "@/lib/sales";
 import { formatPrice } from "@/lib/format";
 import { getLocale } from "@/i18n/locale";
 import { getDictionary } from "@/i18n/get-dictionary";
@@ -119,21 +120,21 @@ export default async function AdminDashboardPage(props: PageProps<"/admin">) {
   ] = await Promise.all([
     prisma.order.aggregate({
       _sum: { totalCents: true },
-      where: { createdAt: { gte: startOfDay() }, status: { not: "STORNIERT" } },
+      where: { createdAt: { gte: startOfDay() }, ...COUNTED_SALE_WHERE },
     }),
     prisma.order.aggregate({
       _sum: { totalCents: true },
-      where: { createdAt: { gte: startOfMonth() }, status: { not: "STORNIERT" } },
+      where: { createdAt: { gte: startOfMonth() }, ...COUNTED_SALE_WHERE },
     }),
     prisma.order.count({
       where: { status: { notIn: ["VERSENDET", "ABGEHOLT", "STORNIERT"] } },
     }),
     prisma.inventory.aggregate({ _sum: { quantity: true } }),
-    prisma.orderItem.aggregate({ _sum: { quantity: true } }),
+    prisma.orderItem.aggregate({ _sum: { quantity: true }, where: { order: COUNTED_SALE_WHERE } }),
     prisma.order.aggregate({
       _avg: { totalCents: true },
       _count: true,
-      where: { status: { not: "STORNIERT" } },
+      where: COUNTED_SALE_WHERE,
     }),
     // Summiert wird in der DATENBANK, nicht hier. Frueher lud diese Abfrage
     // JEDE Bestellposition, die es je gab, samt Produkt-Join in den Speicher,
@@ -150,11 +151,11 @@ export default async function AdminDashboardPage(props: PageProps<"/admin">) {
     // unten); ueber eine Relation laesst sich nicht gruppieren.
     prisma.orderItem.groupBy({
       by: ["productId", "productName"],
-      where: { order: { status: { not: "STORNIERT" } } },
+      where: { order: COUNTED_SALE_WHERE },
       _sum: { quantity: true, totalCents: true },
     }),
     prisma.order.findMany({
-      where: { createdAt: { gte: daysAgo(REVENUE_TREND_DAYS - 1) }, status: { not: "STORNIERT" } },
+      where: { createdAt: { gte: daysAgo(REVENUE_TREND_DAYS - 1) }, ...COUNTED_SALE_WHERE },
       select: { createdAt: true, totalCents: true },
     }),
     // Stammkunden: Kund:innen mit mehr als einer nicht-stornierten Bestellung.
@@ -164,7 +165,7 @@ export default async function AdminDashboardPage(props: PageProps<"/admin">) {
     // machen — mit der Begruendung, Prisma koenne kein HAVING. Es kann.
     prisma.order.groupBy({
       by: ["customerId"],
-      where: { customerId: { not: null }, status: { not: "STORNIERT" } },
+      where: { customerId: { not: null }, ...COUNTED_SALE_WHERE },
       having: { customerId: { _count: { gt: 1 } } },
     }),
     prisma.discountCode.findMany({