fix: validate OpenAIPrompt Java post-processing options

[fallintoplace]

Problem

The java.util.HashMap overload of OpenAIPrompt.setPostProcessingOptions writes the parameter directly, bypassing the inference and validation performed by the Scala Map overload. Java and Py4J callers can therefore create configurations that Scala callers cannot, including regex options without regexGroup and unsupported option maps. The overload also fails to infer postProcessing from valid options.

Changes

• delegate the Java overload to the Scala overload after converting the map
• add isolated unit coverage for CSV mode inference, required regex groups, and invalid option parity between Java and Scala maps

Testing

• cognitive/testOnly com.microsoft.azure.synapse.ml.services.openai.OpenAIPromptParamsSuite (3 tests passed)
• cognitive/Test/scalastyle (0 findings)
• cognitive/Compile/scalastyle (0 findings)

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[github-actions]

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[Copilot]

Pull request overview

This PR fixes inconsistent validation/inference behavior for OpenAIPrompt.setPostProcessingOptions when called from Java/Py4J by delegating the java.util.HashMap overload to the existing Scala Map overload, ensuring both call paths apply the same validation rules and post-processing inference.

Changes:

• Update the Java HashMap overload to delegate to the Scala Map[String, String] overload (restoring validation + mode inference parity).
• Add isolated unit tests covering CSV inference from delimiter, regex requiring regexGroup, and Java/Scala invalid-option parity.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
cognitive/src/main/scala/com/microsoft/azure/synapse/ml/services/openai/OpenAIPrompt.scala	Delegate Java HashMap overload to Scala overload so Java/Py4J callers get the same validation and inference as Scala callers.
cognitive/src/test/scala/com/microsoft/azure/synapse/ml/services/openai/OpenAIPromptParamsSuite.scala	Add targeted tests validating Java overload behavior (mode inference + validation parity).