feat(sales-stats): карточки возвратов в сводке

Две карточки — количество и сумма возвратов за период (красный тон).
Сетку сводки перевёл на 2/5 (10 карточек делятся ровно, без пустых
ячеек). StatCard получил invertDelta: для «меньше — лучше» метрик рост
красится в красный, падение в зелёный (стрелка по факту). 4 локали.

src/api/adminSalesStats.ts

@@ -19,6 +19,8 @@ export interface SalesSummary {
   trial_to_paid_conversion: number;
   renewals_count: number;
   addon_revenue_kopeks: number;
+  refunds_count: number;
+  refunds_kopeks: number;
 }
 
 // ============ Trials ============

src/components/stats/StatCard.tsx

@@ -26,6 +26,9 @@ interface StatCardProps {
   valueClassName?: string;
   /** Optional period-over-period change shown under the value. */
   delta?: StatCardDelta | null;
+  /** For "lower is better" metrics (e.g. refunds): keep the real arrow but flip
+   *  the colour, so a rise reads as bad (red) and a drop as good (green). */
+  invertDelta?: boolean;
 }
 
 export function StatCard({
@@ -35,10 +38,18 @@ export function StatCard({
   tone = 'neutral',
   valueClassName,
   delta,
+  invertDelta = false,
 }: StatCardProps) {
   const toneStyle = TONE[tone];
   const valueClass = valueClassName ?? toneStyle.value;
-  const trendStyle = delta ? (TREND_STYLES[delta.trend] ?? TREND_STYLES.stable) : null;
+  const baseTrend = delta ? (TREND_STYLES[delta.trend] ?? TREND_STYLES.stable) : null;
+  const trendStyle =
+    baseTrend && invertDelta && delta && delta.trend !== 'stable'
+      ? {
+          arrow: baseTrend.arrow,
+          className: TREND_STYLES[delta.trend === 'up' ? 'down' : 'up'].className,
+        }
+      : baseTrend;
 
   return (
     <div className="rounded-xl bg-dark-800/30 p-3 transition-colors hover:bg-dark-800/50">

src/locales/en.json

@@ -1306,7 +1306,9 @@
         "conversion": "Conversion",
         "renewals": "Renewals",
         "addonRevenue": "Add-on Revenue",
-        "manualTopup": "Manual Top-ups"
+        "manualTopup": "Manual Top-ups",
+        "refundsCount": "Refunds",
+        "refundsAmount": "Refunded amount"
       },
       "trials": {
         "total": "Total Trials",

src/locales/fa.json

@@ -1179,7 +1179,9 @@
         "conversion": "تبدیل",
         "renewals": "تمدید",
         "addonRevenue": "درآمد خدمات اضافی",
-        "manualTopup": "شارژ دستی"
+        "manualTopup": "شارژ دستی",
+        "refundsCount": "بازپرداخت‌ها",
+        "refundsAmount": "مبلغ بازپرداخت"
       },
       "trials": {
         "total": "کل آزمایشی",

src/locales/ru.json

@@ -1328,7 +1328,9 @@
         "conversion": "Конверсия",
         "renewals": "Продления",
         "addonRevenue": "Доп. услуги",
-        "manualTopup": "Ручные пополнения"
+        "manualTopup": "Ручные пополнения",
+        "refundsCount": "Возвраты",
+        "refundsAmount": "Сумма возвратов"
       },
       "trials": {
         "total": "Всего триалов",

src/locales/zh.json

@@ -1179,7 +1179,9 @@
         "conversion": "转化率",
         "renewals": "续订",
         "addonRevenue": "附加服务收入",
-        "manualTopup": "手动充值"
+        "manualTopup": "手动充值",
+        "refundsCount": "退款",
+        "refundsAmount": "退款金额"
       },
       "trials": {
         "total": "试用总数",

src/pages/AdminSalesStats.tsx

@@ -13,6 +13,7 @@ import {
   GiftIcon,
   PercentIcon,
   RepeatIcon,
+  ResetIcon,
   RocketIcon,
   SparklesIcon,
   TicketIcon,
@@ -115,6 +116,7 @@ export default function AdminSalesStats() {
       renewals: computeDelta(summary.renewals_count, prevSummary.renewals_count),
       addonRevenue: computeDelta(summary.addon_revenue_kopeks, prevSummary.addon_revenue_kopeks),
       manualTopup: computeDelta(summary.manual_topup_kopeks, prevSummary.manual_topup_kopeks),
+      refunds: computeDelta(summary.refunds_kopeks, prevSummary.refunds_kopeks),
     };
   }, [summary, prevSummary]);
 
@@ -148,7 +150,7 @@ export default function AdminSalesStats() {
           {t('admin.salesStats.loadError')}
         </div>
       )}
-      <div className="grid grid-cols-2 gap-3 sm:grid-cols-4">
+      <div className="grid grid-cols-2 gap-3 sm:grid-cols-5">
         <StatCard
           label={t('admin.salesStats.summary.revenue')}
           value={
@@ -223,6 +225,24 @@ export default function AdminSalesStats() {
           tone="warning"
           delta={deltas?.manualTopup}
         />
+        <StatCard
+          label={t('admin.salesStats.summary.refundsCount')}
+          value={summaryLoading ? '...' : (summary?.refunds_count ?? 0)}
+          icon={<ResetIcon className="h-5 w-5" />}
+          tone="error"
+        />
+        <StatCard
+          label={t('admin.salesStats.summary.refundsAmount')}
+          value={
+            summaryLoading
+              ? '...'
+              : formatWithCurrency((summary?.refunds_kopeks ?? 0) / SALES_STATS.KOPEKS_DIVISOR, 0)
+          }
+          icon={<BanknotesIcon className="h-5 w-5" />}
+          tone="error"
+          delta={deltas?.refunds}
+          invertDelta
+        />
       </div>
 
       {/* Tabs */}