Admin: recompensas de reclutamiento (recruit-a-friend)

- lib/admin-recruit.ts: list/create/delete sobre home_recruitreward
  (required_friends, reward_name, item_id, item_quantity, item_link, icon_class).
- API: POST /api/admin/recruit, DELETE /api/admin/recruit/[id] (403 sin admin).
- UI: /admin/recruit con AdminRecruitManager (alta ordenada por amigos requeridos),
  enlace desde el índice del admin.
- i18n es/en (Admin): 10 claves nuevas.

Verificado: build OK, /admin/recruit 307→login, APIs 403 sin admin,
columnas confirmadas en la migración 0001_initial.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web-next/messages/en.json

@@ -345,7 +345,17 @@
     "unban": "Unban",
     "banReasonPrompt": "Ban reason:",
     "banDaysPrompt": "Ban days (0 = permanent):",
-    "confirmUnban": "Unban {name}?"
+    "confirmUnban": "Unban {name}?",
+    "manageRecruit": "Manage recruit rewards",
+    "recruit": "Recruit-a-friend rewards",
+    "requiredFriends": "Required friends",
+    "rewardName": "Reward name",
+    "itemId": "Item ID",
+    "itemQuantity": "Quantity",
+    "itemLink": "Item link",
+    "iconClass": "Icon class",
+    "noRewards": "No rewards.",
+    "requiredFriendsShort": "{n} friend(s)"
   },
   "Vote": {
     "title": "Vote for us",