Bugfix: Add missing params, change I to I_z, revert tire params to full-scale

[TeoIlie]

What

• Changed I to I_z to standardize, now that the STD and ST param dicts are merged - they have the same meaning, and I_z is more descriptive for "moment of inertia around z-axis"
• Fixed a couple arctan functions to tan to match the commonroad reference code
• For now reverting tire params to full-scale, as the model behaves erratically with the new params

Notes

• The tire parameters still need to be modified for 1/10 scale