fix: fee distributor claim floor fix

[kerber0x]

Description and Motivation

This PR makes the fee distributor use checked_mul_floor when calculating rewards to be distributed. This might fix the issue some users have when claiming rewards.

Related Issues

---

Checklist:

• [x] I have read Migaloo's contribution guidelines.
• [x] My pull request has a sound title and description (not something vague like Update index.md)
• [x] All existing and new tests are passing.
• [x] I updated/added relevant documentation.
• [x] The code is formatted properly cargo fmt --all --.
• [x] Clippy doesn't report any issues cargo clippy -- -D warnings.
• [x] I have regenerated the schemas if needed cargo schema.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 93.20%. Comparing base (78df4e7) to head (ed662e5).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #370 +/- ## ========================================== - Coverage 93.20% 93.20% -0.01% ========================================== Files 219 219 Lines 24860 24859 -1 ========================================== - Hits 23172 23171 -1 Misses 1688 1688 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.