feat: add subscription UI, plan-based nav gating, and client subscription page

- Add plan field to UserInfo shared type
- Subscription API client and React Query hooks
- Client subscription page with status + payment history
- Sidebar navigation filtered by tenant plan features
- Subscription link added to navigation

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

apps/api/src/services/auth.service.ts

@@ -77,6 +77,7 @@ export async function register(data: RegisterRequest): Promise<LoginResponse> {
       tenantId: tenant.id,
       tenantName: tenant.nombre,
       tenantRfc: tenant.rfc,
+      plan: tenant.plan,
     },
   };
 }
@@ -140,6 +141,7 @@ export async function login(data: LoginRequest): Promise<LoginResponse> {
       tenantId: user.tenantId,
       tenantName: user.tenant.nombre,
       tenantRfc: user.tenant.rfc,
+      plan: user.tenant.plan,
     },
   };
 }