Configurer la requête FullText sur Fuseki

Sur recommandation de @tfrancart

https://jena.apache.org/documentation/query/text-query.html

- Adapter la configuration côté Jena Fuseki
- Modifier la requête SPARQL de recherche pour utiliser `text:query`

Cela pourrait aussi résoudre https://github.com/assemblee-virtuelle/semapps/issues/1214

Start with the Jena Fuseki text-query documentation linked in the issue, then locate the Fuseki configuration and the SPARQL search entry point. Done means the Jena Fuseki setup supports FullText search and the search query uses `text:query`; check whether this also addresses issue 1214.

Written by the indexing model from the issue text.