fix: use CAST(FECHA_RECEPCION AS DATE) for Firebird timestamp comparison

FECHA_RECEPCION is a TIMESTAMP field, so comparing directly with
CURRENT_DATE (DATE) always returns 0 rows in Firebird. Cast to DATE first.

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

app/routes/pacientes.py

@@ -55,7 +55,7 @@ LEFT JOIN DIAGNOSTICO d ON TRIM(d.COD_DIAG) = TRIM(r.DIAG_PPAL)
 LEFT JOIN MEDICO m   ON m.CODIGO = r.COD_MEDICO
 JOIN PACIENTE p      ON p.CODIGO = r.COD_PACIENTE
 WHERE TRIM(p.DOCIDENT) = :cedula
-  AND r.FECHA_RECEPCION = CURRENT_DATE
+  AND CAST(r.FECHA_RECEPCION AS DATE) = CURRENT_DATE
 ORDER BY r.IDRECEPCION DESC
 """