WIP ARM with multiple base assets

[naddison36]

Implemented a new multi-base-asset ARM that integrates to Asynchronous Tokenized Vaults (ERC-7540).

Summary

• Added CentrifugeARM.sol as the new concrete Multi Asset ARM.
• Added AbstractMultiAssetARM.sol] as the shared multi-base core.
• Added IAsyncRedeemVault for ERC-7540-style async redeem integrations.

What’s Included

• One shared liquidity asset for LP deposits and withdrawals.
• Multiple supported base assets, each with:
  • its own async redeem vault
  • independent buy price
  • independent sell price
  • independent cross price
• Per-asset admin flows:
  • addBaseAsset
  • removeBaseAsset
  • setPrices
  • setCrossPrice
  • requestVaultRedeem
  • claimVaultRedeem
• Portfolio-level accounting and fees:
  • LP shares still mint/redeem against the common liquidity asset
  • performance fee remains based on net asset growth adjusted for LP flows
  • active lending market remains liquidity-asset-only
• Swap support for liquidityAsset <-> supportedBaseAsset pairs only
• Base-to-base swaps explicitly revert
• Base assets decimals must match the liquidity asset decimals