Insurance module: policy browser (list/search/detail) + renewals view

Plan step 4. Adds the policies API and the Spanish-first /polizas pages on
top of the customer records the customer module already exposes.

API (apps/api/src/policies):
- GET /policies — search over policy number, customer name, agent, vehicle
  license plate, insured-driver name and legacy id; filters for vigencia
  bucket, ramo, aseguradora and liquidation state; five sort orders.
- GET /policies/stats — bucket counts plus premium in force split by
  currency (MXN and USD can't be summed).
- GET /policies/facets — ramos/aseguradoras with counts for the dropdowns.
- GET /policies/:id — full policy plus the owning customer.

Vigencia is derived from policyTo as active/expiring/expired/undated.
"undated" is a real bucket rather than an error case: 528 of the 2378
migrated policies carry no end date at all.

Web:
- /polizas — renewals-first browser; the stat cells double as vigencia
  filters, with a secondary row for ramo, aseguradora and sort order.
- /polizas/[id] — vigencia hero, condiciones y primas, pagos, vehículos,
  asegurados/beneficiarios, siniestros, the verbatim legacy coverage
  columns, and documents.
- Nav gains Clientes | Pólizas with a real active state, and the two
  modules cross-link in both directions.

Also fixes a display bug on the customer detail page: it headlined
policies.total, which is dead data — only 2 of 2378 rows are non-zero
(1585 are literally 0, 791 null), and one of those two is lower than its
own net premium. That rendered "$0.00 Total" on 1585 policies. Premium
headlines and the premium sort now use netPremium (2377/2378 populated);
total is shown only where it is non-zero, as raw source data.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/web/src/lib/api.ts

@@ -7,6 +7,12 @@ import type {
   CustomerDetail,
   CustomerListResponse,
   CustomerStats,
+  PolicyDetail,
+  PolicyFacets,
+  PolicyListResponse,
+  PolicySort,
+  PolicyStats,
+  PolicyStatus,
 } from "./types";
 
 export const API_ORIGIN =
@@ -98,3 +104,53 @@ export function listCustomers(
 export function getCustomer(id: string): Promise<CustomerDetail> {
   return apiFetch<CustomerDetail>(`/customers/${id}`);
 }
+
+/* ------------------------------------------------------ Policies module */
+
+/** Renewal horizon in days, shared by the list, stats and detail calls so the
+ *  "por vencer" bucket means the same thing everywhere. */
+export const EXPIRY_WINDOW_DAYS = 30;
+
+export interface PolicyQuery {
+  query?: string;
+  page?: number;
+  pageSize?: number;
+  status?: PolicyStatus;
+  days?: number;
+  typeId?: string;
+  providerId?: string;
+  liquidated?: boolean;
+  sort?: PolicySort;
+}
+
+export function listPolicies(q: PolicyQuery): Promise<PolicyListResponse> {
+  const params = new URLSearchParams();
+  if (q.query) params.set("query", q.query);
+  if (q.page) params.set("page", String(q.page));
+  if (q.pageSize) params.set("pageSize", String(q.pageSize));
+  if (q.status) params.set("status", q.status);
+  if (q.days) params.set("days", String(q.days));
+  if (q.typeId) params.set("typeId", q.typeId);
+  if (q.providerId) params.set("providerId", q.providerId);
+  if (q.liquidated !== undefined) params.set("liquidated", String(q.liquidated));
+  if (q.sort) params.set("sort", q.sort);
+  const qs = params.toString();
+  return apiFetch<PolicyListResponse>(`/policies${qs ? `?${qs}` : ""}`);
+}
+
+export function getPolicyStats(
+  days: number = EXPIRY_WINDOW_DAYS,
+): Promise<PolicyStats> {
+  return apiFetch<PolicyStats>(`/policies/stats?days=${days}`);
+}
+
+export function getPolicyFacets(): Promise<PolicyFacets> {
+  return apiFetch<PolicyFacets>("/policies/facets");
+}
+
+export function getPolicy(
+  id: string,
+  days: number = EXPIRY_WINDOW_DAYS,
+): Promise<PolicyDetail> {
+  return apiFetch<PolicyDetail>(`/policies/${id}?days=${days}`);
+}