feat(x/fswap): introduce new event(MakeSwapProposal)

[jaeseung-bae]

Description

• Introduce new event for MakeSwapProposal
  • Event includes Swap and DenomMetadata

Motivation and context

How has this been tested?

Screenshots (if appropriate):

Checklist:

• I followed the contributing guidelines and code of conduct.
• I have added a relevant changelog to CHANGELOG.md
• I have added tests to cover my changes.
• I have updated the documentation accordingly.
• I have updated API documentation client/docs/swagger-ui/swagger.yaml

[codecov]

Codecov Report

Attention: Patch coverage is 33.33333% with 4 lines in your changes are missing coverage. Please review.

Project coverage is 69.54%. Comparing base (8ad5585) to head (3b15e93).

❗ Current head 3b15e93 differs from pull request most recent head 43bd287. Consider uploading reports for the commit 43bd287 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1363      +/-   ##
==========================================
- Coverage   69.54%   69.54%   -0.01%     
==========================================
  Files         672      672              
  Lines       56106    56111       +5     
==========================================
+ Hits        39018    39020       +2     
- Misses      14825    14826       +1     
- Partials     2263     2265       +2     

Files	Coverage Δ
x/fswap/keeper/proposal.go	48.54% <33.33%> (-1.46%)	⬇️

... and 1 file with indirect coverage changes

[0Tech]

In my opinion, EventMakeSwap would be more flexible (please consider upcoming msg-based proposals). Then, the emission should reside in MakeSwap.