yams #109550 lazy i18nization of ValidationError [done]

ValidationError should not be internationalized on the yams side, as at this time we may miss information such as end-user language (in terms of cw, think to exception raised on the repository side while the web server use http negociated language).

prioritynormal
typeenhancement
done in0.36.0
load0.500
load left0.000
closed by#23a10f049447 don't translate validation error right away, let one i18n them later by calling exception.tr(trfunc). Closes #109550