fix(dashboard): creditos KPIs show latest month snapshot instead of sum
Saldo insoluto is a balance (like bank balances), not a cumulative metric. The Creditos KD modal now displays the most recent month's values from creditos_tendencia_mensual instead of summing all months. When month filters are active, uses the latest selected month. Vs Periodo Anterior now compares against the previous month.
Co-Authored-By: Claude Opus 4.6 (1M context) noreply@anthropic.com