feat: Add Quarks

[jstoobysmith]

Adding quarks to ./StandardModel, defining their representation under the Lorentz group and under the gauge group.

[github-actions]

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[nateabr]

Overall everything looks great, just some comments on how we could make this approach standard for other particle fields.

I hope they help :)

[nateabr]

Maybe we could define repLorentzGroup with valLineEquiv , such that it can match the style of repGuageGroup .

[jstoobysmith]

Done - agreed!

[nateabr]

awaiting-author

[nateabr]

t-particles

[jstoobysmith]

Many thanks @nateabr

-awaiting-author