As agreed in ML discussion, remove Infinispan as a persistence option.

Maintaining Infinispan support has become an unnecessary toll - dealing with API changes, upgrades, and transitive dependency security vulnerabilities outweighs its benefits. Community consensus was reached to deprecate and remove it.

This simplifies maintenance and allows focus on better-supported options (PostgreSQL, MongoDB). Alternative tech (e.g., Redis) can be considered in the future if needed.