* feat: Add gpt-5.4-mini.
This just adds gpt-5.4-mini at (low/med/high/xhigh) reasoning levels.
* Fix formatting in README for reasoning effort section
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Co-authored-by: Ra's al Ghul <ras@alghul.com>
Co-authored-by: Game_Time <108236317+RayBytes@users.noreply.github.com>