[ATR-26082] Add check of the enabled flag when reading L1 and HLT prescales from JSON into legacy interface

Currently it appears that the TDT reports incorrect information about prescaled chains.

The info is correct in the AOD. It is just misinterpreted when it is read from JSON into the legacy configuration interfaced used by the TDT's internal caches.

Hence disabled chains are being reported incorrectly as PS=1 if queried from the TDT

Enabled chains were not affected, their correct PS was being reported (either PS=1 or PS>1)

Marking draft while more tests are run (but will start a CI too)