Fix conditional router config attribute error

[AndreRatzenberger]

%23%23 🔄 Pull Request

%23%23%23 Describe your Pull Request
Adds the missing feedback_on_failure field to the ConditionalRouterConfig Pydantic model. This resolves an AttributeError that occurred when the router code attempted to access this undeclared property, ensuring the router can correctly handle feedback messages for failed conditions.

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%23%23%23 Is there an existing issue for this%3F

• Existing Issue

If yes, please specify:

Label/Name of the existing issue (if applicable):
Missing feedback_on_failure attribute in ConditionalRouterConfig

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%23%23%23 Please select relevant options:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Improvement

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%23%23%23 Checklist

• My code follows the style guidelines of this project
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I have checked my code and corrected any misspellings