fix price spike check to use correct scaling and compare rates

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 50.00000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 81.84%. Comparing base (0971d8f) to head (23a9093). Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...c/agent0/hyperfuzz/system_fuzz/invariant_checks.py	50.00%	3 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1691 +/- ## ========================================== + Coverage 81.77% 81.84% +0.07% ========================================== Files 99 99 Lines 7647 7650 +3 ========================================== + Hits 6253 6261 +8 + Misses 1394 1389 -5 ``` | [Flag](https://app.codecov.io/gh/delvtech/agent0/pull/1691/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=delvtech) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/delvtech/agent0/pull/1691/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=delvtech) | `81.84% <50.00%> (+0.07%)` | :arrow_up: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=delvtech#carryforward-flags-in-the-pull-request-comment) to find out more.

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