Add pension PDF upload, parsing, and fund summary API

Backend: parse BAC pension statement PDFs (VOL, ROP, FCL) via
pdftotext, store snapshots with duplicate detection, reject
credit card statements. Endpoints: POST /upload, GET /snapshots,
GET /fund-summary.

Frontend: wire up drag-and-drop upload, load real balances and
rendimientos from API, show upload results with error/duplicate
feedback.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/api.ts

@@ -238,3 +238,43 @@ export const getSalarios = (params?: { limit?: number; offset?: number }) =>
   api.get<Transaction[]>('/salarios/', { params });
 export const getSalariosSummary = () =>
   api.get<SalariosSummary>('/salarios/summary');
+
+// --- Pensions ---
+
+export interface PensionSnapshot {
+  id: number;
+  fund: string;
+  contract_number: string;
+  period_start: string;
+  period_end: string;
+  saldo_anterior: number;
+  aportes: number;
+  rendimientos: number;
+  retiros: number;
+  traslados: number;
+  comision: number;
+  correccion: number;
+  bonificacion: number;
+  saldo_final: number;
+  source_filename: string;
+  created_at: string;
+}
+
+export interface PensionUploadResult {
+  imported: number;
+  duplicates: number;
+  errors: string[];
+  snapshots: PensionSnapshot[];
+}
+
+export const uploadPensionPDFs = (files: File[]) => {
+  const form = new FormData();
+  files.forEach((f) => form.append('files', f));
+  return api.post<PensionUploadResult>('/pensions/upload', form);
+};
+
+export const getPensionSnapshots = () =>
+  api.get<PensionSnapshot[]>('/pensions/snapshots');
+
+export const getPensionFundSummary = () =>
+  api.get<PensionSnapshot[]>('/pensions/fund-summary');