feat(mempool): add ZIP-317 rules to mempool

[oxarbitrage]

Motivation

We want to add ZIP-317 relay rules to the mempool verifier, so Zebra can drop transactions before they get into the mempool storage.

Close #5336

Specifications

• https://zips.z.cash/zip-0317#transaction-relaying

Solution

This pull request is checking 2 rules currently:

• Check if transaction unpaid actions is under a threshold.
• Check if the miner fee is greater than the transaction conventional fee.

If there are more rules they need to be added to zebra_chain::transactions::unmined::mempool_checks function.

Review

Reviewer Checklist

• Will the PR name make sense to users?
  • Does it need extra CHANGELOG info? (new features, breaking changes, large changes)
• Are the PR labels correct?
• Does the code do what the ticket and PR says?
  • Does it change concurrent code, unsafe code, or consensus rules?
• How do you know it works? Does it have tests?

Follow Up Work

[codecov]

Codecov Report

Merging #6556 (00b03ad) into main (1461c91) will increase coverage by 0.32%.
The diff coverage is 97.47%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6556      +/-   ##
==========================================
+ Coverage   77.78%   78.10%   +0.32%     
==========================================
  Files         307      309       +2     
  Lines       40273    40621     +348     
==========================================
+ Hits        31325    31727     +402     
+ Misses       8948     8894      -54     

[teor2345]

Looks good, thanks for doing this!
I hope it wasn't too complicated, it seems like updating the tests was a bit of work.

I just want to check where these rules are coming from, to make sure we got them all.

[teor2345]

Thanks for these changes, I am going to go and see what I can do with the fee rate code using the Rust compiler.

[teor2345]

Thanks for this, looks great!