feat: smoother debt ratio for monetary policies

[AlbertoCentonze]

This PR reduces the scope of #107 by doing very minimal and localized changes that are safer to implement.

• Upgrade AggMonetaryPolicy3c to Vyper 0.4.3
• Apply EMA smoothing to the PegKeeper debt ratio used in rate calculations, reducing sensitivity to sudden debt ratio changes and providing more stable interest rates
• Add configurable debt_ratio_ema_time parameter with setter function and getter view
• Add deployer for AggMonetaryPolicy3c in tests
• pyproject.toml: Bump curve-std dependency to include EMA functionality, remove unused ownership-proxy
• tests/utils/deployers.py: Add AGG_MONETARY_POLICY3C_DEPLOYER

This vote adds this new mpol to the system.

• Cleanup monetary policies post deployment (remove the versioning prefix, delete old mpols etc)