feat: implement MinCollateralLiquidity

[toteki]

Description

closes: #1163

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[codecov-commenter]

Codecov Report

Merging #1331 (5480254) into main (6e9fade) will increase coverage by 0.18%.
The diff coverage is 86.53%.

@@            Coverage Diff             @@
##             main    #1331      +/-   ##
==========================================
+ Coverage   51.91%   52.09%   +0.18%     
==========================================
  Files          69       69              
  Lines        6775     6816      +41     
==========================================
+ Hits         3517     3551      +34     
- Misses       2983     2988       +5     
- Partials      275      277       +2     

Impacted Files	Coverage Δ
x/leverage/keeper/grpc_query.go	63.63% <80.95%> (+0.19%)	⬆️
x/leverage/keeper/collateral.go	69.17% <86.95%> (+3.71%)	⬆️
x/leverage/keeper/keeper.go	66.66% <100.00%> (+0.79%)	⬆️
x/leverage/keeper/limits.go	15.62% <100.00%> (ø)

[toteki]

Note: Merge #1329 then #1330 before this

[khoerling]

Looks solid, haven't pulled this down to run locally yet...