Context

Start groups

Nb: we know show all the variants on the photos (we no longer hide them)

sit start: add an icon and put the sit start info before the steepness info
display a "missing line" message when line is missing
variants badge:
- the current problem should show up in the list (and count in the total when we display "xx variants")
- make it easier to go back and forth between variants: the list should be exactly the same (same order)
- see simplified logic