audit(fees): specification audit

[danburck]

Description

As part of an internal audit, this PR refactors the specs of the fees module to improve text flow and add missing parts. For reviewers, please use this as an opportunity to fully understand the fees module.

[linear]

ENG-448 Module Specification audit

Improvements found

• rename key prefixes

  	KeyPrefixFee           => KeyPrefixDeployerAddress
  	KeyPrefixFeeWithdrawal => KeyPrefixWithdrawAddress
  	KeyPrefixInverse       => KeyPrefixContractsByDeployer
  

• Consider changing DevFeeInfo to Fee

[fedekunze]

Looks good, the only thing to point out is that 50% of the total tx fee goes to the validator instead of 50% of the base fee (which applies only to DynamicFeeTx (EIP-1559)).

Ideally, it should be:

• For Legacy and AccessList txs: 50% should go to the validator and 50% to the developer (i.e same logic as now)
• For DynamicFeeTx: Fee = BaseFee + PriorityFee. 50% of the BaseFee should go to the validator and 50% to the developer. 100% of the PriorityFee should go to the validator. Right now it's 50/50 for the Fee.

EDIT: it's fine as we leave it as is for now and we create an issue to work on it in the future

[danburck]

@fedekunze nice, added an issue: https://linear.app/evmos/issue/ENG-468/priority-fees-should-go-to-validators-for-dynamicfeetx