[repository] set .eid on eschema when schema is loaded from the filesystem enforcing the contract that a repository's schema should have .eid attribute of entity schema set to the eid of the entity used to serialize them in the db. Before this cset, this was not true during tests or for some c-c commands where 'quick_start' is set (eg db-restore, i18ncube...). The change in server __init__ makes this assumption true during instance creation: the serializing code was actually setting eid on schema object, but a reference to a previously built schema was given instead of the one for the latest created repository. Closes #10450092

TACHES
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-- écrire objet stocke/manipule les données

-- extraire tests de chaîne de caractère

* utiliser sqlite 

* écrire fonction prend chemin en argument et renvoie contenu

* extraire tests (chaîne de caractère) de spec 

* utiliser yams pour schéma