New MuCh geometry v23b

New MuCh geometry v23b is created to resolve the large computational time of v23a geometry, and provides MuCh lmvm setup. Please approve the macro code in the directory cbmroot/geometry/macro/much/fair.

Attaching here the updated macro, where overlap issue is now resolved and for C-plate is also implemented.create_MUCH_geometry_v23b_lmvm.C

Presentations regarding v23a geometry which is here being replaced.

https://indico.gsi.de/event/19193/contributions/77251/attachments/46178/65744/20240125_SWM_MUCH.pdf https://indico.gsi.de/event/19193/contributions/77251/attachments/46178/65747/Geometrical%20modifications%20summary%20for%20Software%20Meeting%2025th%20Jan%202024.pdf

Link to presentation on 2025-10-23 at 46th CBMCM regarding https://indico.gsi.de/event/20881/contributions/93520/attachments/53270/80219/cbm_much_geo.pdf