maksymovchynnikov/SensCalc: v1.3

1. Revised the phenomenology of vector mediators: added production via fragmentation (see ref. 2409.11096) as opposed to the production "via mixing with vector mesons" (see 1810.01879).
2. Added the proper implementation of CHARM searches for diphotons.
3. Added E137 experiment and the electron bremsstrahlung production mode (to be tested).
4. Added the explanations for variations of setups of the same experiment (e.g., SHiP-ECN3, SHiP-ECN4) in notebook 1.
5. Added explanations and references defining the models with LLPs implemented in SensCalc in notebook 1.
6. Added explanations and references for the description of various LLP production modes in notebook 2. 
7. Added the uncertainty for the DIS production mechanism for dark photons, mediators coupled to the baryon current, ALPs coupled to gluons and fermions (see Refs. 2409.11096, 2310.03524, 2501.04525 for discussion).
8. Added the models of Higgs-like scalars, HNLs, and ALPs coupled to photons to the EventCalc module.
9. Added new production modes of ALPs coupled to gluons and ALPs universally coupled to fermions: proton bremsstrahlung, decays of various mesons, quark fragmentation (following 2501.04525), as opposed to the previously used outdated description "via mixing" (following 2201.05170).
10. Re-organized the notebooks. Now, notebook 1 imports all available descriptions of the LLP decays, asks users to select those to be used for further calculations, and, for each of them, produces tabulated acceptances. These are then used to calculate the tabulated number of events, sensitivities and their uncertainty bands in notebook 3. Notebook 4 produces the plots with uncertainty bands coming from the theoretical uncertainty in production and decay. 
11. Added uncertainties for the description of decays of Higgs-like scalars following 2407.13587.
12. Added a new signature for calculating the decay products acceptance: decays with just one detectable particle (`mono-particle`).
13. Added two new LLP models: inelastic dipole DM and vector mediators coupled solely to the baryon current.
14. Fixed mistakes and bugs: missing factor of 2 in the calculation of the number of scalars from the decay h -> S+S; the number of omega mesons (in the previous version, the number of phi mesons has been used instead); mistake in decay modes for the mediators coupled to the baryon current; using the unit matrix elements for 3-body decays of dark photons instead of the proper ones; bugs coming from updating to Mathematica 14.+, incl. crash in case of displaying the experimental setup in notebook 1 (temporarily - just commenting out the plot of the setup); computing the sensitivity from bremsstrahlung and Drell-Yan for dark photons even if these production channels have not been selected.