feat: add admin dashboard revenue chart and fix empty customer order bug

shop/components/admin/recent-orders.tsx

@@ -4,6 +4,7 @@ import { useEffect, useState, useRef } from 'react'
 import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card'
 import { Badge } from '@/components/ui/badge'
 import Link from 'next/link'
+import { RevenueChart } from './revenue-chart'
 
 type RecentOrder = {
   id: string
@@ -34,6 +35,7 @@ const POLL_INTERVAL_MS = 30_000
 
 export function AdminRecentOrders() {
   const [orders, setOrders] = useState<RecentOrder[]>([])
+  const [chartData, setChartData] = useState<{ name: string; value: number }[]>([])
   const [newOrderIds, setNewOrderIds] = useState<Set<string>>(new Set())
   const [lastChecked, setLastChecked] = useState<Date>(new Date())
   const knownIds = useRef<Set<string>>(new Set())
@@ -43,7 +45,7 @@ export function AdminRecentOrders() {
       const baseUrl = process.env.NEXT_PUBLIC_BASE_URL || 'http://localhost:3000';
       const res = await fetch(`${baseUrl}/api/admin/recent-orders`, { cache: 'no-store' });
       if (!res.ok) return
-      const { orders: fresh } = await res.json()
+      const { orders: fresh, chartData: freshChart } = await res.json()
 
       // Neue Bestellungen erkennen (Highlight)
       const freshIds = new Set<string>(fresh.map((o: RecentOrder) => o.id))
@@ -54,6 +56,7 @@ export function AdminRecentOrders() {
       knownIds.current = freshIds
 
       setOrders(fresh)
+      setChartData(freshChart || [])
       setNewOrderIds(newOnes)
       setLastChecked(new Date())
 
@@ -76,12 +79,10 @@ export function AdminRecentOrders() {
     <div className="grid gap-4 md:grid-cols-2 lg:grid-cols-7">
       <Card className="col-span-4 glass-dark border-white/5">
         <CardHeader>
-          <CardTitle>Übersicht</CardTitle>
+          <CardTitle>Übersicht (letzte 6 Monate)</CardTitle>
         </CardHeader>
         <CardContent className="pl-2">
-          <div className="h-[200px] flex items-center justify-center text-slate-400 italic">
-            [Umsatz-Chart – folgt in nächstem Update]
-          </div>
+          <RevenueChart data={chartData} />
         </CardContent>
       </Card>