if "Fin de mission is empty ... add an alert ""Fin de Mission" : Un client ouvert ne peut être supprimé"   and do not delete it
add on the colum Statut the image red or green like you have done yesterday for type = "Mandat Spécifique"
On the confirm message to delete of the client, add the name of the client before the confirmation
Add validation on V03-283-I - N° TVA Tiers, V05-LIC - N° TVA Tiers, DEB Exped - N° Identification de l'acquéreur CEE, V09-DES - N° TVA Tiers
on DEB Intro ( and only this one), delete the field "N° identification acquéreur CEE"
nature_transaction select option list. remove CEE field. fix should empty field validation.