feat: admin password change with confirmation in team panel

Add "Admin Actions" section (superadmin-only, collapsed by default) with
password + confirm fields, eye toggle, mismatch validation, and success toast.
Delete button moved here too.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/src/i18n/ar.json

@@ -234,6 +234,10 @@
   "team.defaultPassword": "افتراضياً: changeme123",
   "team.confirmPassword": "تأكيد كلمة المرور",
   "team.passwordsDoNotMatch": "كلمتا المرور غير متطابقتين",
+  "team.adminActions": "إجراءات المسؤول",
+  "team.newPassword": "كلمة مرور جديدة (٦ أحرف على الأقل)",
+  "team.changePassword": "تغيير كلمة المرور",
+  "team.passwordChanged": "تم تغيير كلمة المرور بنجاح",
   "team.optional": "(اختياري)",
   "team.fixedRole": "دور ثابت للمديرين",
   "team.remove": "إزالة",