feat: admin partner settings page, partner section visibility toggle, custom requisites text

- New AdminPartnerSettings page with validation (pattern from AdminTicketSettings)
- Settings gear button on AdminPartners header
- Hide partner/withdrawal sections when partner_section_visible is false
- Use custom requisites_text as label in withdrawal form
- i18n keys for ru/en

src/pages/AdminPartners.tsx

@@ -41,10 +41,34 @@ export default function AdminPartners() {
       {/* Header */}
       <div className="mb-6 flex items-center gap-3">
         <AdminBackButton to="/admin" />
-        <div>
+        <div className="flex-1">
           <h1 className="text-xl font-semibold text-dark-100">{t('admin.partners.title')}</h1>
           <p className="text-sm text-dark-400">{t('admin.partners.subtitle')}</p>
         </div>
+        <button
+          onClick={() => navigate('/admin/partners/settings')}
+          className="rounded-lg bg-dark-800 p-2 text-dark-400 transition-colors hover:bg-dark-700 hover:text-dark-200"
+          title={t('admin.partners.settings')}
+        >
+          <svg
+            className="h-5 w-5"
+            fill="none"
+            viewBox="0 0 24 24"
+            stroke="currentColor"
+            strokeWidth={1.5}
+          >
+            <path
+              strokeLinecap="round"
+              strokeLinejoin="round"
+              d="M9.594 3.94c.09-.542.56-.94 1.11-.94h2.593c.55 0 1.02.398 1.11.94l.213 1.281c.063.374.313.686.645.87.074.04.147.083.22.127.324.196.72.257 1.075.124l1.217-.456a1.125 1.125 0 011.37.49l1.296 2.247a1.125 1.125 0 01-.26 1.431l-1.003.827c-.293.24-.438.613-.431.992a6.759 6.759 0 010 .255c-.007.378.138.75.43.99l1.005.828c.424.35.534.954.26 1.43l-1.298 2.247a1.125 1.125 0 01-1.369.491l-1.217-.456c-.355-.133-.75-.072-1.076.124a6.57 6.57 0 01-.22.128c-.331.183-.581.495-.644.869l-.213 1.28c-.09.543-.56.941-1.11.941h-2.594c-.55 0-1.02-.398-1.11-.94l-.213-1.281c-.062-.374-.312-.686-.644-.87a6.52 6.52 0 01-.22-.127c-.325-.196-.72-.257-1.076-.124l-1.217.456a1.125 1.125 0 01-1.369-.49l-1.297-2.247a1.125 1.125 0 01.26-1.431l1.004-.827c.292-.24.437-.613.43-.992a6.932 6.932 0 010-.255c.007-.378-.138-.75-.43-.99l-1.004-.828a1.125 1.125 0 01-.26-1.43l1.297-2.247a1.125 1.125 0 011.37-.491l1.216.456c.356.133.751.072 1.076-.124.072-.044.146-.087.22-.128.332-.183.582-.495.644-.869l.214-1.281z"
+            />
+            <path
+              strokeLinecap="round"
+              strokeLinejoin="round"
+              d="M15 12a3 3 0 11-6 0 3 3 0 016 0z"
+            />
+          </svg>
+        </button>
       </div>
 
       {/* Stats Overview */}