Process - Quic - fix invalid return code from add_quic()

[SiskaPavel]

Summary

Fix add_quic() function invalid return code that caused pipeline infinite loop

Details

Fix invalid return code in add_quic() that caused possibility the processing pipeline to enter an infinite loop.
The function previously returned internal QUIC status codes that were not properly handled by the pipeline.

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✅ Checks

• [ ] Relevant documentation was updated (if needed)
• CI pipeline passes (build, tests, lint, static analysis)
• New code follows clang-tidy rules
• The change is clearly related to a specific issue / requirement
• [ ] Documentation (e.g. Doxygen) is updated if needed
• The PR is rebased on the latest master
• No unrelated changes are included

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