feat(x/ecocredit/marketplace): marketplace fee API

[aaronc]

Description

Defines the protobuf API for marketplace fees.

In this model there are buyer a seller percentage fees for every marketplace sale. If the buyer fee is 5% and the seller fee is 5% and 100tokens of credits are sold, the buyer pays an extra 5tokens totaling a payment of 105tokens and the seller receives 95tokens. 10tokens would be deposited in the fee pool. If the denom is uregen, then the 10uregen get burned.

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[JeancarloBarrios]

I think to start with is perfect!

[robert-zaremba]

added comment to clarify a unit

[aaronc]

Thanks @robert-zaremba. Addressed your comments

[robert-zaremba]

utACK

[codecov]

Codecov Report

Attention: 18 lines in your changes are missing coverage. Please review.

Comparison is base (1636a79) 73.19% compared to head (c9622e3) 73.11%.

❗ Current head c9622e3 differs from pull request most recent head e416771. Consider uploading reports for the commit e416771 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2151      +/-   ##
==========================================
- Coverage   73.19%   73.11%   -0.08%     
==========================================
  Files         234      236       +2     
  Lines       13802    13820      +18     
==========================================
+ Hits        10102    10105       +3     
- Misses       2960     2976      +16     
+ Partials      740      739       -1     

Files	Coverage Δ
...redit/marketplace/keeper/msg_gov_set_fee_params.go	0.00% <0.00%> (ø)
...dit/marketplace/types/v1/msg_gov_set_fee_params.go	0.00% <0.00%> (ø)

... and 1 file with indirect coverage changes