fix(sidecar): process pending bundle diffs

[merklefruit]

Overview

When validating requests containing multiple transactions, we need to take into account the previous transactions in the bundle as increasing the nonce (and decreasing the balance) of the account that sent it, even if they haven't been committed yet to the template.

This fixes the issue by introducing two maps to keep track of the pending state due to these requests.

Note that if anything in the request fails validation, the whole bundle won't be committed, as expected.

Tests

• currently testing from this branch in release candidate v0.1.3-alpha.rc2
• multiple type 2 txs: Included: https://dora.helder-devnets.xyz/slot/273556

[thedevbirb]

Thanks for the PR! The changes make sense. If you have time, can please add some unit tests with bundles?

[mempirate]

Lgtm!