feat: Add keeper methods for historacle prices and medians

[rbajollari]

Description

closes: #1540

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[codecov-commenter]

Codecov Report

Merging #1548 (fbb76be) into main (acad48b) will increase coverage by 0.59%.
The diff coverage is 75.53%.

@@            Coverage Diff             @@
##             main    #1548      +/-   ##
==========================================
+ Coverage   51.59%   52.18%   +0.59%     
==========================================
  Files          71       72       +1     
  Lines        6923     7111     +188     
==========================================
+ Hits         3572     3711     +139     
- Misses       3081     3126      +45     
- Partials      270      274       +4     

Impacted Files	Coverage Δ
x/oracle/keeper/params.go	60.86% <0.00%> (-29.46%)	⬇️
x/oracle/types/keys.go	42.10% <0.00%> (-57.90%)	⬇️
x/oracle/keeper/historic_price.go	93.81% <93.81%> (ø)
x/oracle/types/params.go	97.40% <94.44%> (-2.60%)	⬇️

[adamewozniak]

initial review - great job @rbajollari !!

[robert-zaremba]

Blocking because:

• adding historical price is super inefficient (see comment)
• have concerns about state bloat: how the state will be managed and cleaned?
• why do we have one big median? Shouldn't we have median per "epoch"?

Is there any spec clarifying the pruning functionality? If not, I can help with that if needed.

[adamewozniak]

this looks good to me, just a few comments.

I'd like to have a review from @zarazan , and maybe @toteki or @RafilxTenfen as well 🙏

dismissing in the interest of time - this lgtm, we still have to figure out how to separate this in the build process (in another PR)

[adamewozniak]

waiting for a review from @RafilxTenfen to merge 🙏

[RafilxTenfen]

Just one comment
utACK 💯