Add Arize OSS Phoenix integration

[nate-mar]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

There's a good set of llm observability platforms out there right now. Dify currently integrates with Langfuse and Langsmith. This issue is to propose adding integration with Arize OSS Phoenix to give Dify users another option. Note: I work with the Phoenix team.

This has also been requested by the community in an issue on the Phoenix repo: Arize-ai/phoenix#5299 (also mentioned by the same user in the dify repo: #10434).

Happy to take this one on myself :)

2. Additional context or comments

No response

3. Can you help us with this feature?

• I am interested in contributing to this feature.