feat: mtcs sends messages to overdraft contract

[dangush]

Working on integrating MTCS and overdrafts so that transfers are reflected as balance changes in the mtcs-overdraft contract.

Closes informalsystems/cycles-protocol#38

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This PR is completed and ready for review when it is:

• Merged with Peppi's escrow contracts branch to ensure compatibility

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TODO

Short Term

• Fix listening script to query correct epoch-indexed storage keys
• Write a script for deploying and instantiating the overdraft + membership contracts
• Remove overdrafts contract from contract state <- decide where granting mtcs ownership over liquidity sources gets handled
• Align code changes with Peppi's escrow PR and merge the two
• Add setter for overdraft owner so that MTCS can be added post-instantiation
• Working overdrafts clearing with MTCS
• understand what causes the sequence mismatch error and make sure it doesn't show up again

Blocked / questions

• working message attestations
• Handle setoffs correctly according to persistence
  • In $ -> Alice -> Bob -> $ scenario, what should happen with the Alice -> Bob setoff notice?
  • The A -> B obligation needs to be updated before persisted to the next epoch.
  • Blocked on "epoch persistence"
• Clean up the rust script for generating encrypted obligations. What should the final form of this look like?

Long Term

• Rewrite memberships contract to better suit our needs (replace member vec with map, remove 'weights')

[hu55a1n1]

@dangush Is this PR superseded by the work currently on the cycles-protocol repo (main branch)? If so can we close this?

[hu55a1n1]

Closing because the MTCS app work is now happening on the cycles-protocol repo. (And this should already be on main there)