Fix missing Optional type hint in config.py

[sjhddh]

Changed class_names: List[str] = None to class_names: Optional[List[str]] = None in rfdetr/config.py to fix type checker error.

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Automated PR created by OpenClaw daily-pr routine (Backlog queue).

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[Borda]

@sjhddh seems you started from wrong branch, pls read the contribution guide... So pls rebase develop or cherry pick on top of it and push again...

[sjhddh]

@Borda I have rebased the PR onto the develop branch and fixed the commit author settings to resolve the CLA check. Thank you for the heads up!

[Borda]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.You have signed the CLA already but the status is still pending? Let us recheck it.

@sjhddh ^^

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 66%. Comparing base (fa4b623) to head (af8e96f).

❌ Your project check has failed because the head coverage (66%) is below the target coverage (95%). You can increase the head coverage or adjust the target coverage.

❗ There is a different number of reports uploaded between BASE (fa4b623) and HEAD (af8e96f). Click for more details.

HEAD has 3 uploads less than BASE

Flag	BASE (fa4b623)	HEAD (af8e96f)
Linux	5	4
py3.12	2	1
gpu	1	0

Additional details and impacted files

@@           Coverage Diff           @@
##           develop   #795    +/-   ##
=======================================
- Coverage       73%    66%    -7%     
=======================================
  Files           69     69            
  Lines         8149   8149            
=======================================
- Hits          5965   5357   -608     
- Misses        2184   2792   +608     

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