chore: cleanup todos that should be panic

[tisonkun]

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What's changed and what's your intention?

TRIVIAL AS IS.

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR does not require documentation updates.

[codecov]

Codecov Report

Attention: Patch coverage is 54.54545% with 5 lines in your changes are missing coverage. Please review.

Project coverage is 85.16%. Comparing base (d123791) to head (b101c37).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3720      +/-   ##
==========================================
- Coverage   85.44%   85.16%   -0.29%     
==========================================
  Files         966      966              
  Lines      162087   162087              
==========================================
- Hits       138496   138039     -457     
- Misses      23591    24048     +457