Add Opik

[anmorgan24]

Comet recently sunset CometLLM and in its place launched Opik, a tool with most of the same capabilities as the old CometLLM but with a whole host of additional features and capabilities. This PR updates the readme accordingly.

Signed-off-by: Abby Morgan [email protected]

What is this tool for?

1. Store test cases as datasets and run experiments on them
2. Provide human feedback to responses via the SDK or UI
3. Use Opik’s built-in LLM-as-a-judge for hallucination detection, moderation, and RAG evaluation
4. Run evaluations as part of your CI/CD pipeline using the PyTest integration
5. Close the feedback loop by adding error traces to your evaluation datasets.

What's the difference between this tool and similar ones?

Opik combines the features of many individual tools currently in the space into one fully open source tool, with options for enterprise support and deployment packages.

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