feat(legal): wire recurrent-payments document + restore footer link

Backend now serves a dedicated recurring-payments legal document, so:
- Add adminLegalPagesApi.get/updateRecurrentPayments and infoApi.getRecurrentPayments
  (+ InfoVisibility.recurrent).
- AdminLegalPages: new 'Рекуррентные платежи' editor tab (DocumentEditor now driven
  by a DOCUMENT_API dispatch map instead of privacy/offer ternaries).
- PublicLegal: add 'recurrent' doc; add public /recurrent-payments route.
- Re-add the recurrent link to the login LegalFooter (was removed pending backend).
- i18n: admin.legalPages.tabs.recurrent for ru/en/fa/zh (footer.recurrent already existed).

type-check, eslint, prettier and build all pass.

src/api/adminLegalPages.ts

@@ -111,6 +111,23 @@ export const adminLegalPagesApi = {
     return response.data;
   },
 
+  getRecurrentPayments: async (): Promise<LegalDocumentResponse> => {
+    const response = await apiClient.get<LegalDocumentResponse>(
+      '/cabinet/admin/legal-pages/recurrent-payments',
+    );
+    return response.data;
+  },
+
+  updateRecurrentPayments: async (
+    data: LegalDocumentUpdateRequest,
+  ): Promise<LegalDocumentResponse> => {
+    const response = await apiClient.put<LegalDocumentResponse>(
+      '/cabinet/admin/legal-pages/recurrent-payments',
+      data,
+    );
+    return response.data;
+  },
+
   getRules: async (): Promise<AdminRulesResponse> => {
     const response = await apiClient.get<AdminRulesResponse>('/cabinet/admin/legal-pages/rules');
     return response.data;

src/api/info.ts

@@ -23,6 +23,11 @@ export interface PublicOfferResponse {
   updated_at: string | null;
 }
 
+export interface RecurrentPaymentsResponse {
+  content: string;
+  updated_at: string | null;
+}
+
 export interface ServiceInfo {
   name: string;
   description: string | null;
@@ -42,6 +47,7 @@ export interface InfoVisibility {
   rules: boolean;
   privacy: boolean;
   offer: boolean;
+  recurrent: boolean;
 }
 
 export const infoApi = {
@@ -75,6 +81,14 @@ export const infoApi = {
     return response.data;
   },
 
+  // Get recurring-payments document
+  getRecurrentPayments: async (): Promise<RecurrentPaymentsResponse> => {
+    const response = await apiClient.get<RecurrentPaymentsResponse>(
+      '/cabinet/info/recurrent-payments',
+    );
+    return response.data;
+  },
+
   // Get service info
   getServiceInfo: async (): Promise<ServiceInfo> => {
     const response = await apiClient.get<ServiceInfo>('/cabinet/info/service');