Simplify variable selection frontend

[Femkemilene]

At the moment, variable selection is complicated in two senses:

1. A distinction is made between simple, detailed and all variables.
2. Search is either on the variable abbreviations or on the variable names.

I believe we agreed on removing the distinction between simple and detailed variables. Would it be helpful to make search simpler too by allowing a simultaneous search on abbreviations and written out variable names?

[jp-camecon]

Agree on removing the simple detailed all distinction and just showing all variables.

On variable vs code, probably the simplest option is we could merge the names and descriptions together to avoid needing to switch between code and name?

[Femkemilene]

Merging the names and codes would be good, yeah.