Specialisation calculation overhaul b

[Accidental-Explorer]

Brief Description of What This PR Does

• Take into account hex size so that a cell using advanced organelles isn't likely to have a lower bonus automatically.
• Exclude the nucleus from the calculation because its large size would have too large an influence due to above change. And realistically, having a nucleus does not really make any cell "less specialised".
• Remove the minimum size required to trigger the specialisation effect. This prevents the sudden jump going from 5 to 6 organelles and makes design of sub-6 hex cells a bit more interesting. I also don't think this has a dangerously big effect, since the bonus rises gradually from 0 anyway.
• Took a different calculation: Simpson's Diversity Index, commonly used for things like species diversity in an ecosystem or market monopolisation. Still favours focusing on one organelle over others, but 8-2 is judged as better than 8-1-1.

Tooltip not adjusted yet.

Of course, this version starts you off with the maximum bonus, reducing whenever you add a different new organelle, which might not feel great.

Alternative overhaul:
#6801
#6806

Less extreme changes:
#6800

Related Issues

• Switching to eukaryotic organelles lowers specialisation bonus
• There's an unexpected sudden jump in process speeds when you reach 6 organelles and trigger the specialisation system.
• Currently, removing non-relevant organelles is not necessary for "specialisation" until very large cells sizes.
• In fact, it could be said that the system provides a strong incentive to just making larger cells.
• Currently, there is no incentive against having many different organelle types in a cell.

Progress Checklist

Note: before starting this checklist the PR should be marked as non-draft.

• PR author has checked that this PR works as intended and doesn't
  break existing features:
  https://wiki.revolutionarygamesstudio.com/wiki/Testing_Checklist
  (this is important as to not waste the time of Thrive team
  members reviewing this PR)
• Initial code review passed (this and further items should not be checked by the PR author)
• Functionality is confirmed working by another person (see above checklist link)
• Final code review is passed and code conforms to the
  styleguide.

Before merging all CI jobs should finish on this PR without errors, if
there are automatically detected style issues they should be fixed by
the PR author. Merging must follow our
styleguide.