feat(operator): sklearn testing operator

[aglinxinyuan]

Introduce the Sklearn Testing Operator, which accepts any number of machine learning models (from 1 to n) and computes accuracy, F1 score, precision, and recall for each model, appending these metrics to the output columns.

There is a port dependency between the model and the data: the data port must be finished first. The data table is then used as an internal state for testing. This operator can accept any number of models; each model will be tested against the same data table.

Input single model:

Input multiple models:

[Copilot]

Pull Request Overview

This PR adds a new “Sklearn Testing” operator that computes common evaluation metrics on a collected dataset using a provided scikit-learn model.

• Introduces SklearnTestingOpDesc with Python code generation for accuracy, F1, precision, and recall.
• Registers the new operator in the logical operator registry.
• Extends the output schema to include the computed metric fields.

Reviewed Changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 2 comments.

File	Description
core/workflow-operator/src/main/scala/edu/uci/ics/amber/operator/sklearn/testing/SklearnTestingOpDesc.scala	New operator descriptor for Sklearn testing with codegen and schema updates
core/workflow-operator/src/main/scala/edu/uci/ics/amber/operator/LogicalOp.scala	Added registration of the Sklearn Testing operator

Comments suppressed due to low confidence (1)

core/workflow-operator/src/main/scala/edu/uci/ics/amber/operator/sklearn/testing/SklearnTestingOpDesc.scala:33

• This new operator does not appear to have any associated unit or integration tests; adding test coverage for typical and edge-case scenarios would help ensure correctness.

class SklearnTestingOpDesc extends PythonOperatorDescriptor {

[Yicong-Huang]

This operator's design can be further discussed.

[aglinxinyuan]

Had offline discussions.
We will NOT add this version of the testing op for now, but I might change it to the "regular" version later.