Add APGD (possibly wrapped and native)

[maurapintor]

• Wrap from original implementation / robustbench
• Add custom implementation with tracking
• Eventually add other wrapped versions (e.g., adv_lib)

[lucascionis]

Implementation Plan:

• [x] Wrap APGD attack from AutoAttack: requires adding AutoAttack as Backend
• [ ] Evaluate the possibility of implementing APGD natively