[BUGFIX] Correction de bugs critiques dans la classe config

[kwizer15]

Description

• Correction du décryptage des clés API dans byKeys()
• Amélioration de la gestion du cache dans la méthode remove() pour le nettoyage complet lors de la suppression avec "*"
• Ajout d'une limite de taille dans genKey() pour éviter les problèmes de performance

Cette mise à jour corrige plusieurs problèmes qui pouvaient impacter la sécurité et les performances.

Suggested changelog entry

• Fixed API key decryption in byKeys() method
• Improved cache cleanup when removing configurations with "*"
• Added size limit to key generation to prevent performance issues

Related issues/external references

N/A

Types of changes

• Bug fix (non-breaking change which fixes)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
  • This change is only breaking for integrators, not for external standards or end-users.
• Documentation improvement

PR checklist

• I have checked there is no other PR open for the same change.
• I have read the [La ligne directrice pour contribuer à ce projet / Contribution guidelines for this project).
• I grant the project the right to include and distribute the code under the GNU.
• I have added tests to cover my changes.
• I have verified that the code complies with the projects coding standards.
• [Required for new sniffs] I have added MD documentation for the sniff.