[Misc] Clean up duplicated hf overrides

[Isotr0py]

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• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
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Purpose

• Clean duplicate hf_overrides used to create model with only one layer.

Test Plan

Test Result

(Optional) Documentation Update

[gemini-code-assist]

Code Review

This pull request effectively refactors duplicated hf_overrides functions into a single, centralized utility, which is a great improvement for maintainability. The implementation correctly consolidates the logic from the previous versions. I've identified a critical issue regarding a potential TypeError and a high-severity issue for improving type hinting in the new utility function. Addressing these will make the new function more robust and the code easier to maintain.

[github-actions]

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[DarkLight1337]

Thanks for the cleanup!