Set priority for eth transactions

[yihuang]

Description

Set the tx priority to the lowest priority in the messages.

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[facs95]

Unit tests are failing @yihuang 🙏

[codecov]

Codecov Report

Merging #1214 (4c760a3) into main (8d3a2b1) will increase coverage by 0.01%.
The diff coverage is 71.11%.

@@            Coverage Diff             @@
##             main    #1214      +/-   ##
==========================================
+ Coverage   57.19%   57.21%   +0.01%     
==========================================
  Files          94       94              
  Lines        8399     8419      +20     
==========================================
+ Hits         4804     4817      +13     
- Misses       3351     3356       +5     
- Partials      244      246       +2     

Impacted Files	Coverage Δ
x/evm/types/access_list_tx.go	88.96% <0.00%> (-1.18%)	⬇️
x/evm/types/dynamic_fee_tx.go	89.94% <0.00%> (ø)
x/evm/types/legacy_tx.go	90.83% <0.00%> (-1.41%)	⬇️
x/evm/types/tx_data.go	97.91% <ø> (ø)
x/evm/keeper/utils.go	66.23% <69.56%> (-1.38%)	⬇️
app/ante/eth.go	80.05% <100.00%> (+0.43%)	⬆️
app/ante/handler_options.go	79.45% <100.00%> (ø)
x/evm/keeper/keeper.go	81.25% <100.00%> (+0.23%)	⬆️

[fedekunze]

LGTM, would be great to add more integration tests and update the specification. Some remarks

1. I see the case for some applications that might not want to enable the prioritized mempool so in that scenario, we should add a parameter to the EVM to disable tx prioritization
2. Do we need to update the Cosmos ante handler to enable prioritization?

[yihuang]

• I see the case for some applications that might not want to enable the prioritized mempool so in that scenario, we should add a parameter to the EVM to disable tx prioritization

The validator is still free to choose the v0 mempool which is FIFO, ignore the priority field.

• Do we need to update the Cosmos ante handler to enable prioritization?

The cosmos ante handler has a default mechanism to extract prioritization from fees directly, in another PR we'll customize that one with feemarket.

[fedekunze]

We should add specific integration tests for tx prioritization before we can merge this:

• legacy and access list txs
• dynamic fee tx with 0 and > 0 priority tip

We also need to update the specification for the EVM with more details about tx prioritization for Ethereum msgs

[yihuang]

We should add specific integration tests for tx prioritization before we can merge this:

• legacy and access list txs
• dynamic fee tx with 0 and > 0 priority tip

added a priority integration test, which checked that a higher priority tx gets included first even if sent later.

We also need to update the specification for the EVM with more details about tx prioritization for Ethereum msgs

added sth in feemarket's spec in the ante handlers section.

[fedekunze]

ACK. @facs95 @alexanderbez can you review?