Bug: Adapt aNCA Units Column Mapping to PKNCA new system

[Gero1999]

Description

Currently the app allows already units column mapping (avalu, doseu, rrltu). However, inside the app these variables are currently being processed by just taking the first value of the column. Whenever the new PKNCA v0.11.0.9 release happens on CRAN we can update the App to adapt to how now the app defines in PKNCAconc and PKNCAdose the untis (concu, doseu, timeu & amountu) by doing it for each row. Adapt the code accordingly and include amountu if neccesary

To reproduce

Use any ADNCA file with multiple units defines, see how only one of them will be used for the interpretation of the concentration/time/dose columns when you run NCA and obtain the results.

Expected behaviour

If you load a dataset with multiple units defined for different rows, then they should be considered accordingly for the NCA running.

Indeed, if multiple analytes have already been implenented (#3), it is also expected that each analyte has their own standard units definition, which will impact on the parameter resulting units.