[spencer-tb]

Description

Fixes three latent bugs that surface on the first Amsterdam-era transition with a blob schedule or base fee rule change (Amsterdam to Bogota with EIP-8198): base_fee_change_calculator misses reachable base fees (round-down short on increases, off by one gas on exact decreases), test_reserve_price_at_transition predicts the fork block's base fee with the parent fork's rule, and test_fork_transition_excess_blob_gas_post_blob_genesis gives the destination-creating blob transaction too little gas for Amsterdam's new-account state gas. All existing fixtures are unchanged.

Related Issues or PRs

Found on #3703.

Checklist

• Ran fast static checks to avoid CI fails, see Code Standards & Verifying Changes: just static
• PR title has the form <type>(<area>): <title>, where <type> and <area> come from an appropriate C-<type>, respectively A-<area>, label. The title should match the target squash commit message.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.93%. Comparing base (f329cb4) to head (124a272).

Additional details and impacted files

@@              Coverage Diff              @@
##           forks/bogota    #3721   +/-   ##
=============================================
  Coverage         94.93%   94.93%           
=============================================
  Files               672      672           
  Lines             40846    40846           
  Branches           3775     3775           
=============================================
  Hits              38776    38776           
  Misses             1439     1439           
  Partials            631      631           

Flag	Coverage Δ
unittests	94.93% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[marioevz]

LGTM, thanks for the fixes. I took the opportunity to do some quality-of-life improvements to the tests touched, and also fixed the approach of adding the account creation state cost by using a pre-funded account instead.
I'll try to re-target the branch to forks/bogota and then merge.