feat: add Merit claim and airdrop distribution for AAVE boosted token

[Xeonus]

AAVE Technical team informed us that for ceritain boosted pools, there will be Merit rewards claimable via Merkl. These airdrops are claimable once a month. They whitelisted our Omni multi-sig to claim on vault v3's behalf.

What we need to do:

• Check Merit campaign claims for AAVE boosted pool tokens (e.g. PyUSD)
• Perform same pool snapshot logic as for other airdrops
• Claim with Omni and distribute accordingly

Cadence of Merit claims is once a month

[Xeonus]

Detailed technical specifications

Merit rewards

Aaves direct incentive program. Most rewards run on a monthly cadence and are claimable via Merkl. The campaign dashboard incl. historical campaigns can be consulted here: https://apps.aavechan.com/merit

pyUSD

• Omni multi-sig as claimer whitelisted
• Cadence: monthly claim, see Merit page: https://apps.aavechan.com/merit/ethereum-supply-pyusd
• PyUSD rewards already claimable via Omni, see https://app.merkl.xyz/user/0x9ff471f9f98f42e5151c7855fd1b5aa906b1af7e

• Eligible pool: https://balancer.fi/pools/ethereum/v3/0x64b84023cfe8397df83c67eaccc2c03ecda4aee5

ETHx

• Omni-sig as claimer whitelisted.
• No rewards (yet)
• Cadence: monthly, see https://apps.aavechan.com/merit/ethereum-supply-ethx
• Eligible pool: https://balancer.fi/pools/ethereum/v3/0x4ab7ab316d43345009b2140e0580b072eec7df16