[evaluation] red team user agent for RAI service calls (#42127)

* Initial plan

* Implement red team user agent for RAI service calls

Co-authored-by: slister1001 <[email protected]>

* Conform red team user agent to Azure AI Evaluation SDK format

- Updated user agent to use format: azure-ai-evaluation/1.9.0 (type=redteam; subtype=RedTeam)
- Leverages existing add_useragent_product infrastructure
- Maintains backward compatibility with existing evaluator patterns
- Removes separate red team user agent string in favor of standard SDK format

Co-authored-by: slister1001 <[email protected]>

* Remove unused USER_AGENT constant from red team constants

Co-authored-by: slister1001 <[email protected]>

* Run black code formatter to fix formatting issues

Co-authored-by: slister1001 <[email protected]>

* Run black code formatter

* Implement ability for caller to update red team user agent

Co-authored-by: slister1001 <[email protected]>

* Remove redteam_context_with_product method as requested

Co-authored-by: slister1001 <[email protected]>

* Implement user_agent parameter support in red team scan method

Co-authored-by: slister1001 <[email protected]>

* Run black code formatter

* Update sdk/evaluation/azure-ai-evaluation/azure/ai/evaluation/_user_agent.py

Co-authored-by: Copilot <[email protected]>

* Update sdk/evaluation/azure-ai-evaluation/azure/ai/evaluation/red_team/_red_team.py

Co-authored-by: Copilot <[email protected]>

* Simplify user agent handling by removing redteam_context method and inlining logic

Co-authored-by: kdestin <[email protected]>

* black formatter

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Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: slister1001 <[email protected]>
Co-authored-by: Copilot <[email protected]>
Co-authored-by: kdestin <[email protected]>

Author: 4 people