[Frontend] Add /classify endpoint

[frieda-huang]

FIX #13567 (#13567)

[github-actions]

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[DarkLight1337]

Some initial comments. Can you also add an example script to examples/online_serving to show how to use this endpoint?

[frieda-huang]

Some initial comments. Can you also add an example script to examples/online_serving to show how to use this endpoint?

Yes! It's openai_classification_client.py under examples/online_serving.

[DarkLight1337]

examples/online_serving to show how to use this endpoint?

Oh, right. Sorry I missed that

[frieda-huang]

examples/online_serving to show how to use this endpoint?

Oh, right. Sorry I missed that

Really appreciate the feedback! I’ve implemented your suggestions in the latest commit.

I’ve noticed that serving_classification.py, serving_score.py, serving_transcription.py, and serving_embedding.py all share the same pattern of input preprocessing, request scheduling, and result‑generator aggregation. Should we move that pipeline into a shared helper or abstract base class?

[DarkLight1337]

It's not really following OpenAI API so let's rename this to ServingClassification

[DarkLight1337]

I’ve noticed that serving_classification.py, serving_score.py, serving_transcription.py, and serving_embedding.py all share the same pattern of input preprocessing, request scheduling, and result‑generator aggregation. Should we move that pipeline into a shared helper or abstract base class?

Sure!