Fix eval sample when include_sample_schema is True, we are evaluati…

[YusakuNo1]

…ng the generated result from agent

Description

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[Copilot]

Pull request overview

This PR fixes a bug in the agent evaluation sample where the evaluator was incorrectly referencing {{item.response}} instead of {{sample.output_text}} when include_sample_schema is set to True. When evaluating agents with azure_ai_target_completions, the agent's generated response is available in the sample object (specifically sample.output_text), not in the item object which only contains the input data defined in the item_schema.

Key changes:

• Updated data mapping in violence detection evaluator to use {{sample.output_text}} instead of {{item.response}}