daily data capture plot assign colors

when there aren't any invalid days all the data shows as red (eg Haley Park 2023). this is counter-intuitive -> one would expect invalid days to show as red and valid days as blue. this happens automatically when there is at least one invalid day but not otherwise. the fix is to manually set the factor levels and assign colors.

No file or test is named. Start by locating the daily data capture plot and inspecting how day validity is converted to factor levels and colors. Done means valid days consistently appear blue and invalid days red, including when there are no invalid days.

Written by the indexing model from the issue text.