refactor: remover código morto e exports não utilizados

Remove 6 componentes não utilizados (dashboard-grid, expenses/income
by category widgets, installment analysis panels, fatura-warning-dialog).

Remove funções/tipos não utilizados: successResult, generateApiToken,
validateApiToken, getTodayUTC/Local, formatDateForDb, getDateInfo,
calculatePercentage, roundToDecimals, safeParseInt/Float, isPeriodValid,
getLastPeriods, normalizeWhitespace, formatCurrency wrapper,
InboxItemInput, InboxBatchInput, ProcessInboxInput, DiscardInboxInput,
LancamentosColumnId, 5 funções de anticipation-helpers.

Redireciona imports de formatCurrency para lib/lancamentos/formatting-helpers.

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

lib/actions/types.ts

@@ -5,16 +5,6 @@ export type ActionResult<TData = void> =
 	| { success: true; message: string; data?: TData }
 	| { success: false; error: string };
 
-/**
- * Success result helper
- */
-export function successResult<TData = void>(
-	message: string,
-	data?: TData,
-): ActionResult<TData> {
-	return { success: true, message, data };
-}
-
 /**
  * Error result helper
  */