SPRINGFIELD — A new lawsuit alleges state leaders violated the Illinois Constitution when they failed to approve a spending plan.It also contends they violated the state constitution when they approved a partial spending plan.Either way, the 37 social service groups who filed the claims in St. Clair County Court this week want a judge to order they be paid in the absence of a state budget.They argue they have just as much right — perhaps more of a right — than the state workers who are currently being …