merge ribbons

[SimonDanisch]

This is a quick and dirty PR mostly done with claude to merge all meshes into one, instead of using hundreds of surface plots.
This is required to render larger molecules with TraceMakie (or RayMakie I want to call it I think).
It seems to work well, but of course I have no idea if this breaks anything else.

[codecov]

Codecov Report

❌ Patch coverage is 98.46154% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 53.74%. Comparing base (e255502) to head (84759d3).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
src/ribbon/render.jl	98.41%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #58      +/-   ##
==========================================
+ Coverage   50.00%   53.74%   +3.74%     
==========================================
  Files          13       13              
  Lines         608      655      +47     
==========================================
+ Hits          304      352      +48     
+ Misses        304      303       -1     

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[AntonOresten]

This is great! Thanks.

Would this make reactive ribbons any easier? I struggled with this in the past, and considered merging whole ribbons into a single surface, creating gaps with NaNs. I think this is a better solution though. I have also not looked at ComputeGraph yet.