feat: Use LookupMap instead of UnorderedMap for storing positions

[petarvujovic98]

API Changes

Removes the list_borrows and list_supplys methods

[github-actions]

Staging contract is deployed to gh-110.templar-in-training.testnet account

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Gas Report

harvest_yield

Iterations	Gas
0	3.0 Tgas
391	7.7 Tgas

Estimated snapshot limit: 23561

apply_interest

Iterations	Gas
0	2.9 Tgas
391	16.4 Tgas

Estimated snapshot limit: 8168

[petarvujovic98]

@peer2f00l Do you want to have a service storing data to a DB for easier retrieval from the frontend? This would just be a convenience service, so doesn't affect the actual behavior?

[peer2f00l]

@petarvujovic98 We do not, and you are correct that this does not affect the integral behavior of the contract.

I think we can set up such a service, or use a preexisting indexer service. I have actually been discussing this performance improvement with @SmolinPavel , and had not yet decided on whether to pull the trigger. Regardless, even an indexer service is not necessarily required, since the account IDs can be scraped from the storage keys on the contract.