Enhance user management and billing integration

- Updated the `UserSummaryDto` to include `BillingEnabled` and `BillingPaidUntil` properties, allowing for better tracking of user billing status.
- Refactored the `IdentityService` to populate the new billing fields when retrieving user summaries.
- Modified the dashboard and admin user management components to display billing information, including a link to the billing page and a badge for billing status.
- Added internationalization support for new billing-related labels in both English and Russian.
- Ensured frontend components reflect the updated user data structure, enhancing user experience with billing visibility.

frontend/src/routes/admin/users.tsx

@@ -5,6 +5,7 @@ import { useTranslation } from 'react-i18next'
 import { Input } from '@/shared/ui/input'
 import { Button } from '@/shared/ui/button'
 import { Badge } from '@/shared/ui/badge'
+import { PaidUntilBadge } from '@/features/billing/PaidUntilBadge'
 import { listUsers } from '@/features/admin/users/api'
 import { UserManageDialog } from '@/features/admin/users/UserManageDialog'
 import type { UserSummaryDto } from '@/shared/api/types'
@@ -56,6 +57,7 @@ function AdminUsersPage() {
                 <th className="py-2 font-medium">{t('admin.users.userName')}</th>
                 <th className="py-2 font-medium">{t('admin.users.role')}</th>
                 <th className="py-2 font-medium">{t('admin.users.statusLabel')}</th>
+                <th className="py-2 font-medium">{t('admin.users.billingLabel')}</th>
                 <th className="py-2" />
               </tr>
             </thead>
@@ -73,6 +75,13 @@ function AdminUsersPage() {
                           : t('admin.users.status.pending')}
                     </Badge>
                   </td>
+                  <td className="py-2">
+                    {user.billingEnabled ? (
+                      <PaidUntilBadge paidUntil={user.billingPaidUntil} />
+                    ) : (
+                      <span className="text-muted-foreground">—</span>
+                    )}
+                  </td>
                   <td className="py-2 text-right">
                     <Button size="sm" variant="outline" onClick={() => setManaging(user)}>
                       {t('admin.users.manage')}