feature[frontend]: improve printing of materials and material library

[groberts-flex]

Improving of material printing to address feature request #2307.

import tidy3d as td

mat = td.material_library["W"]["RakicLorentzDrude1998"]
slab = td.Structure(
        geometry=td.Box(
            center=(0, 0, 0),
            size=(1, 1, 1),
        ),
        medium=mat,
    )

print("\n\nPrinting mat:")
print(mat)
print("\n\nPrinting slab with mat as medium:")
print(slab)

medium_dict = {"medium" : mat}
print("\n\nPrinting dict holding medium:")
print(medium_dict)

print("\n\n")

Output:

Printing mat:

td.PoleResidue(
	eps_inf=1.0, 
	poles=((0j, (4.2732115514080845e+17+0j)), ((-97233116671752.14+0j), (-4.2732115514080845e+17+0j)), ((-402605873718973.75-1471252666401400j), 7403002173803196j), ((-973090800441519.4-2745063931489722.5j), 1.2197111799530032e+16j), ((-2531099568361548-4814146946972908j), 2.9579221430831016e+16j), ((-4433222413252700-1.0493429699239636e+16j), 4.978330061510858e+16j)), 
	frequency_range=(24176811129032.258, 1208986804855426.0))

Printing slab with mat as medium:

attrs={} geometry=Box(attrs={}, type='Box', center=(0.0, 0.0, 0.0), size=(1.0, 1.0, 1.0)) name=None background_permittivity=None background_medium=None type='Structure' medium=W_RakicLorentzDrude1998

Printing dict holding medium:

{'medium': W_RakicLorentzDrude1998}

[groberts-flex]

thanks for starting me off with this util.py file @yaugenst-flex. Made some minor modifications, but overall it works well!

[yaugenst-flex]

Neat! Didn't think of this approach, but that looks great.

[yaugenst-flex]

Bit confused by this property, what's its purpose?

[yaugenst-flex]

I feel like this is a bit too technical for this change, maybe focus more on the impact this has on usability. Maybe something like "Named mediums now display by name for brevity; materials/variants print concise summaries including references."

[yaugenst-flex]

Not sure what this test does? __repr__ is never called here no?

[yaugenst-flex]

Now that I'm thinking about this some more I feel like we should do two, optionally three things:

1. A concise __str__ representation that is pretty similar to the one currently. Maybe even shorter, like just a list of the material names. Not sure. Tbh if we have the below, might also just skip it entirely for the material library and just print the dict instead.
2. A .show(), .describe(), or .pretty_print() (just throwing some names out there) method that prints a nicely formatted summary using rich. For the material library as a whole that could be e.g. a table. We already use rich in other places so this would not be an additionaly dependency.
3. Optionally (but definitely nice), a _repr_pretty_ method (see here) to ensure nicely formatted output in jupyter notebooks too. I think this can largely reuse whatever we do in 2.

[yaugenst-flex]

These are mostly smoke tests, which are good to have but it'd be good if we would also test some functionality, e.g. if the material names are what we think they are, whether the __repr__ returns the string, what it does for None...
The variants and material library are a bit more annoying, we should still check if e.g. some expected strings are in there or not.

[yaugenst-flex]

Thanks @groberts-flex, this is much needed! I think the changes to the Medium work well as-is, and thanks for adding all the material names! Regarding pretty printing within the material library itself I added some more comments because I think we should try to make this output as pretty and useful as we can if we're already working on it. But all in all it's looking pretty good!