Moved cluster max width to a constant rather than an option

The max width of the clustering (4) is, realistically, a constant of the FT operations. Moving this to FT constants makes the code more coherent (and technically removes a running-time variable).

Needed for LHCb!4084 (merged)

mentioned in merge request LHCb!4084 (merged)

• [2023-04-25 15:02] Validation started with lhcb-master-mr#7696

approved this merge request

merged

mentioned in commit 96f7d480