Contract with an arbitration clause entered into solely between the insured and the third party that caused the damage. Subrogation action brought by the insurer subrogated to the rights of the insured. Transmissibility of the arbitration agreement through subrogation of the insurer to the rights and actions of the insured, in light of Article 786 of the Civil Code. Claim by the insurer against the third party subject to the arbitration clause: