We ported to pydantic 2.* by importing pydantic.v1, but it would be good to do a full port.

There are many internals that utilize v1 features, so it's an opportunity to dive pretty deep into the front end code, convert them to v2 syntax, and potentially simplify them if they are not needed anymore or there are simpler ways to handle them.

I took a stab at it here but couldn't get it 100% working and there are some loose ends I'm not 100% sure about. It's also possible these changes messed with our docs build, I didn't check that yet.

@daquinteroflex depending on how much time you have, maybe after the docs merging and poetry, we can try wrapping this up and that will help us future-proof tidy3d.