feat: add support for OPENAI_ORGANIZATION and OPENAI_PROJECT env vars

[rumple]

Added support for OpenAI-Organization and OpenAI-Project headers through environment variables, allowing users with multiple organizations to specify which organization and project to use for API requests.

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❌ @amrut
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[rumple]

recheck

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I have read the CLA Document and I hereby sign the CLA

[rumple]

recheck

[rumple]

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[tibo-openai]

recheck

[tibo-openai]

There is an issue due to

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also CI / tests do not seem to pass. Could you have a look?

[tibo-openai]

@rumple Looks like this has drifted, could you look at freshening this up and resolving the merge conflicts?

[rumple]

Recheck

[rumple]

@tibo-openai Not sure what is missing here. Can you help?