feat(dashboard): add pending/upcoming expenses table

- Backend: GET /expenses/pending-upcoming returns PENDING expenses with dueDate <= today+5 days, classified as overdue/upcoming
- DashboardExpensesTable: groups by periodicExpenseId, shows summed totals with status badges, links to /expenses?periodicExpenseId=X
- Expenses route accepts ?periodicExpenseId search param and pre-selects it in the filter
- fix: BeloAnalysisPage DatePicker type mismatch

apps/frontend/src/lib/api.ts

@@ -208,6 +208,14 @@ export function getExpenses(
   return fetcher<PaginatedResponse<Expense>>(`/api/expenses${qs ? `?${qs}` : ""}`);
 }
 
+export type PendingUpcomingExpense = Expense & {
+  dueType: "overdue" | "upcoming";
+};
+
+export function getPendingUpcomingExpenses(): Promise<PendingUpcomingExpense[]> {
+  return fetcher<PendingUpcomingExpense[]>("/api/expenses/pending-upcoming");
+}
+
 export function getTotalPending(): Promise<MonthlyExpensesTotal> {
   return fetcher<MonthlyExpensesTotal>("/api/expenses/pending-total");
 }