Replace home workflow steps with 2026 impact stats (Task #23)

The home page previously showed the 10-step "خطوات إقفال دورة التبرع"
workflow section. The user asked to replace it with an "إحسانكم لعام 2026"
impact statistics section matching the attached reference.

Changes:
- artifacts/ehsan-poc/src/pages/home.tsx: removed the 10-step workflow
  section and added an "Impact Statistics" section in its place — a centered
  heading with a green Leaf accent, a subtitle, and three rounded white
  shadowed stat cards (lucide icons HandHeart / Users / Wallet), each with a
  large green value and a label. Responsive 3-up grid stacking on mobile.
- artifacts/ehsan-poc/src/lib/i18n/translations.ts: added a `home.stats`
  group (title, subtitle, and the 3 value/label pairs) in both en and ar.
  AR values: 85,4 مليون / 391,5 ألف / 3.113 مليار. EN mirrors with Million /
  Thousand / Billion.

Notes:
- Static reference numbers used as display values (POC; no live data — per
  task out-of-scope).
- No emojis; lucide icons consistent with the rest of the app. The old
  t.home.workflowTitle and t.workflow.* keys are left in place (harmless
  shared strings) but are no longer used by the home page.

Verified: tsc --noEmit clean; e2e confirmed AR + EN rendering, old workflow
section removed, no console errors.

artifacts/ehsan-poc/src/lib/i18n/translations.ts

@@ -257,6 +257,16 @@ export const en = {
     heroBrowse: "Browse Opportunities",
     featuredTitle: "Featured Opportunities",
     noResults: "No opportunities match your search.",
+    stats: {
+      title: "Your EHSAN in 2026",
+      subtitle: "Statistics reflecting the impact of your giving through the EHSAN platform in 2026",
+      donationsValue: "85.4 Million",
+      donationsLabel: "Number of Donations",
+      beneficiariesValue: "391.5 Thousand",
+      beneficiariesLabel: "Number of Beneficiaries",
+      totalValue: "3.113 Billion",
+      totalLabel: "Total Donations",
+    },
   },
   workflow: {
     step1: "Request Submitted",
@@ -674,6 +684,16 @@ export const ar = {
     heroBrowse: "تصفّح الفرص",
     featuredTitle: "الفرص المميزة",
     noResults: "لا توجد فرص تطابق بحثك.",
+    stats: {
+      title: "إحسانكم لعام 2026",
+      subtitle: "إحصائيات تعكس أثر عطائكم عبر منصة إحسان لعام 2026",
+      donationsValue: "85,4 مليون",
+      donationsLabel: "عدد عمليات التبرع",
+      beneficiariesValue: "391,5 ألف",
+      beneficiariesLabel: "عدد المستفيدين",
+      totalValue: "3.113 مليار",
+      totalLabel: "إجمالي التبرعات",
+    },
   },
   workflow: {
     step1: "مقدم الطلب",