Draft: setting custom ComboHypo names as from the core menu code

This change tries to fix the Control Flow rule that wants unique sequences of Filter + menuSequence + ComboHypo. The BLS signature has custom ComboHypos that break this rule because they reuse the same instance of CH (same name, same DH) for all the steps. After discussions, we agree that this exception of the rule can be accepted because the custom BLS CH are able to distinguish the input data handles, and the current code is safe.

Take it as draft for future developments.

related to !74723