fix: return error instead of panic for behaviors triggered by client (backport #1395)

[mergify]

Description

closes: #XXXX

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

---

This is an automatic backport of pull request #1395 done by [Mergify](https://mergify.com).

[codecov]

Codecov Report

Attention: Patch coverage is 25.00000% with 9 lines in your changes are missing coverage. Please review.

Project coverage is 69.37%. Comparing base (3e73dfe) to head (7775f10).

Additional details and impacted files

@@               Coverage Diff                @@
##           release/v0.49.x    #1400   +/-   ##
================================================
  Coverage            69.37%   69.37%           
================================================
  Files                  675      675           
  Lines                70052    70058    +6     
================================================
+ Hits                 48596    48603    +7     
- Misses               19168    19169    +1     
+ Partials              2288     2286    -2     

Files	Coverage Δ
x/fbridge/keeper/transfer.go	78.46% <100.00%> (+6.58%)	⬆️
x/fbridge/keeper/genesis.go	8.57% <0.00%> (-0.26%)	⬇️
x/fbridge/keeper/auth.go	55.64% <25.00%> (+0.37%)	⬆️
x/fbridge/keeper/abci.go	0.00% <0.00%> (ø)