Draft: BandQ development for 2025 first reoptimisation (Superseded by !4070)

Superseded by !4070

Notice: 2024-patches is not merged into master yet, namely the central EoY resprucing development not in master yet. Please do not start your work based on bandq_2025_reoptimisation for now, which could cause many conflicts when merging this MR to master. We will remove this statement when it's safe to start working on a branch based on bandq_2025_reoptimisation .

Aiming for %Reoptimised Hlt2 selections for 2025: "lossless" first pass.

This MR should be ready around 1 week before December LHCb week.

Please create an MR targetting on bandq_2025_reoptimisation and ping Yajing and Mengzhen for review.

Existing updates:

• added 6 Xib0, Xib-, Omb- decay modes (resolving #879 (closed))
• fixed am_min 5780 -> 5580 in Xib lines including general function make_xib2cx_for_spectroscopy
• added shortcut functions tight_track (as in bandq_EoY_sprucing), charm_dm and Cst_or_tight_track