collect tap ravs

[hopeyen]

• Import escrow contracts npm package
• Add sequelize schema and resolvers for scalar_tap_ravs; updated relations between Voucher and AllocationSummary to be compatible with RAV.
• Define SignedRAV as the equivalence of TAPVerifier.SignedRAVStruct == EIP712SignedMessage<ReceiptAggregateVoucher>
• RAV processing triggered alongside AllocationReceiptCollector's voucher processing which is in indexer-agent.
• Add EventualAllocations and EscrowContracts to AllocationReceiptCollector
• Obtain typed final SignedRAVs from DB, loop through individual SignedRav for individual submissions on-chain
• Refactored allocationSigner function to provide Signer for computing allocationIDProof as required by escrow.redeem
• transactionManager to first estimate gas and then execute transaction to contracts.escrow.redeem(signedRAV, allocationIDProof)
• Upon getting transaction receipt, go ahead deleting RAV from DB.
• Basic metrics added for RAV

[fordN]

Sorry this is a bit nitpicky: can we keep the commit format consistent with how we've been working in this repo?
<package-name>: <Description of commit>

For example:
agent: Fix bug in stake usage calculation

[gusinacio]

Continuation of PR is gonna be on #869