feat(huggingface): add qa and ranking tasks

[anishshiva7]

⚠️ This PR is stacked on hf/04-audio-mediagen. Until that lands, the diff below may also include earlier HuggingFace task-family changes depending on which base GitHub is showing. The new code in this PR is codegen/QaRankingCodegen.scala, the QA/ranking-related additions to codegen/PythonCodegenBase.scala, the new QA/ranking fields on HuggingFaceInferenceOpDesc.scala, and the QA/ranking task tests in HuggingFaceInferenceOpDescSpec.scala. Once PR 4 merges and this PR is retargeted to main, the diff should auto-clean to the PR 5 QA/ranking changes only.

What changes were proposed in this PR?

Adds the QA/ranking/classification task family — 5 HF pipeline tasks — as a new TaskCodegen plugged into the dispatcher established by the text-generation PR:

QA tasks: question-answering, table-question-answering

classification/ranking tasks: zero-shot-classification, sentence-similarity, text-ranking

codegen/QaRankingCodegen.scala supplies the per-task payload + parse Python branches for all 5 tasks.

CodegenContext is extended with contextColumn, candidateLabels, and sentencesColumn (EncodableString).

HuggingFaceInferenceOpDesc.scala gains 3 new @JsonProperty fields and registers QaRankingCodegen in the dispatcher.

PythonCodegenBase.scala grows to host the shared QA/ranking infrastructure:

• Per-row validation for the new column-named fields.
• question-answering payload handling with prompt + context.
• table-question-answering payload handling with table data.
• zero-shot-classification payload handling with candidate labels.
• sentence-similarity and text-ranking payload handling with sentence inputs.
• Response parsing for QA/ranking outputs.

User-input strings continue to flow through pyb"..." + EncodableString so they reach Python as self.decode_python_template('<base64>') rather than raw literals. PythonCodeRawInvalidTextSpec still passes with 117/117 descriptors py_compile cleanly.

Any related issues, documentation, or discussions?

Tracking issue: Add HuggingFace question answering and ranking tasks apache#5292

Closes Add HuggingFace question answering and ranking tasks apache#5292

Stacked on: PR 4 audio/media generation tasks / hf/04-audio-mediagen

Parent issue: Add Hugging Face inference operator apache#5041

Closed sibling issue: Add HuggingFaceModelResource REST endpoints for HF operator UI apache#5134

How was this PR tested?

sbt "WorkflowOperator/compile; WorkflowOperator/Test/compile" clean.

sbt "WorkflowOperator/testOnly org.apache.texera.amber.operator.huggingFace.HuggingFaceInferenceOpDescSpec org.apache.texera.amber.util.PythonCodeRawInvalidTextSpec" — 31 focused tests pass, including HuggingFace QA/ranking task coverage and the raw Python descriptor scan.

sbt "WorkflowOperator / scalafmtCheck" clean.

sbt "WorkflowOperator / Test / scalafmtCheck" clean.

PythonCodeRawInvalidTextSpec — 117/117 descriptors py_compile cleanly with the new operator code paths, no marker leaks.

Was this PR authored or co-authored using generative AI tooling?

Yes, co-authored with generative AI tooling (Codex).

[github-actions]

👋 Thanks for your first contribution to Texera, @anishshiva7!

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