Add PEtab SciML logo

[sebapersson]

Adds a logotype for PEtab-SciML. The design aims to stay visually consistent with the main PEtab logo, using the same font, blue color, and table layout, while incorporating a neural network graphic to represent the SciML component. A dark-mode variant is also included for use in the docs and on GitHub (both have a dark-theme).

Most of the changes in the README is due to my markdown auto-formatting in vs-code.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.01%. Comparing base (29d8737) to head (51256f8).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #85   +/-   ##
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  Coverage   94.01%   94.01%           
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  Files           6        6           
  Lines         301      301           
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  Hits          283      283           
  Misses         18       18           

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[dilpath]

Looks good! Thanks. Fine as is but for a single logo, one could add a stroke to the "SciML" text so it appears well on both light and dark background.

[BSnelling]

The font looks different between the .png and .svg versions (serif vs sans-serif)?

[sebapersson]

The font looks different between the .png and .svg versions (serif vs sans-serif)?

We confirmed this is a local issue (might be due to not having the font installed). We are using a non-standard font (Cabin), but to avoid this problem for users all references I have now updated the PR to use the PNG version in all places.

[sebapersson]

Fine as is but for a single logo, one could add a stroke to the "SciML" text so it appears well on both light and dark background.

I think it looks a bit better with specific logos for light and dark (very hard to find universally best colors, e.g., the PEtab blue is not perfect for dark), so lets keep two logos :)