perf: otimizar dashboard com indexes, cache e consolidação de queries (v1.3.0)

- Adicionar indexes compostos em lancamentos para queries frequentes
- Eliminar ~20 JOINs com pagadores via helper cacheado getAdminPagadorId()
- Consolidar queries: income-expense-balance (12→1), payment-status (2→1), categories (4→2)
- Adicionar cache cross-request via unstable_cache com tag-based invalidation
- Limitar scan de métricas a 24 meses
- Deduplicar auth session por request via React.cache()

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

components/dashboard/top-expenses-widget.tsx

@@ -16,7 +16,8 @@ type TopExpensesWidgetProps = {
 	cardOnlyExpenses: TopExpensesData;
 };
 
-const formatTransactionDate = (date: Date) => {
+const formatTransactionDate = (date: Date | string) => {
+	const d = date instanceof Date ? date : new Date(date);
 	const formatter = new Intl.DateTimeFormat("pt-BR", {
 		weekday: "short",
 		day: "2-digit",
@@ -24,7 +25,7 @@ const formatTransactionDate = (date: Date) => {
 		timeZone: "UTC",
 	});
 
-	const formatted = formatter.format(date);
+	const formatted = formatter.format(d);
 	// Capitaliza a primeira letra do dia da semana
 	return formatted.charAt(0).toUpperCase() + formatted.slice(1);
 };