doc: improve example notebook presentation

[jacanchaplais]

Description of changes

Basic demo:

• Added heading structure
• Stated intended learning outcomes
• Included description of function composition with JAX compatibility

CFD demo:

• Added heading structure
• Stated intended learning outcomes
• Brief explanation of what's going on
• Replaced verbose print output with tqdm
• Included @jpbrodrick89's very cool LBFGS optimiser
• Embedded animation for interactive play in Jupyter Notebook

Testing done

None.

License

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.00%. Comparing base (613c84d) to head (78bf3d9).
Report is 1 commits behind head on main.

Additional details and impacted files

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  Coverage   89.00%   89.00%           
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  Files           3        3           
  Lines         200      200           
  Branches       24       24           
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  Hits          178      178           
  Misses         11       11           
  Partials       11       11           

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[jacanchaplais]

Apologies for the incorrect title, and the lack of running pre-commit hooks. I just installed them, so the next push should rectify.

I am currently working on the unchecked boxes in the PR description.

For the animation display, it does work in the Notebook, however as it renders an interactive widget, the GitHub preview does not display it. I could just display it as a GIF, which might work better for people perusing on GitHub?