feat(landing-stats): rebuild charts on shared components + add funnel & breakdowns

The landing stats page rendered raw recharts by hand plus a bespoke progress-bar
list, looking nothing like the Sales/Remnawave stats. Rebuild it on the shared
chart components and add the visualizations the data warrants:

- Daily: MultiSeriesAreaChart (created/paid) + SimpleAreaChart (revenue),
  replacing the hand-rolled area chart and the custom progress-bar list.
- Tariff & traffic sources: BreakdownList; payment methods & gift composition:
  DonutChart — all the same components Sales stats uses.
- New conversion Funnel (created → paid) and a Gift activation card
  (claimed/sent + rate), backed by the new backend breakdowns.
- Containers use the bento-card surface; i18n added in ru/en/zh/fa.

src/locales/en.json

@@ -3978,6 +3978,12 @@
         "dailyChart": "Purchases & Revenue by Day",
         "tariffChart": "Tariff Distribution",
         "giftBreakdown": "Gifts vs Regular",
+        "funnelTitle": "Conversion funnel",
+        "giftClaimTitle": "Gift activation",
+        "giftClaimLabel": "claimed / sent",
+        "dailyRevenue": "Daily revenue",
+        "byPaymentMethod": "By payment method",
+        "bySource": "Traffic sources",
         "purchases": "Purchases",
         "revenueLabel": "Revenue",
         "gifts": "Gifts",