fix(go): compat_oai plugin returns incomplete history when streaming

[MikeRez0]

Changes fix this issue
#4683

Checklist (if applicable):

• PR title is following https://www.conventionalcommits.org/en/v1.0.0/
• Tested (manually, unit tested, etc.)
• Docs updated (updated docs or a docs bug required)

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[gemini-code-assist]

Code Review

This pull request updates the generateStream and convertChatCompletionToModelResponse functions in go/plugins/compat_oai/generate.go to accept and utilize the ai.ModelRequest object, ensuring the request context is preserved in the model response. A review comment identifies that the signature change for convertChatCompletionToModelResponse breaks the generateComplete function, which was not updated in this PR. The feedback includes a code suggestion to fix the compilation error and improve error handling by wrapping errors with contextual information.

[MichaelDoyle]

Thanks @MikeRez0! Can you get the CLA taken care of? In the mean time we'll get the review done.

[MikeRez0]

Already signed

[MikeRez0]

@apascal07 Hi, Alex! Can you review changes, please? I want to use stream mode in my project

[apascal07]

A few requested changes:

1. Keep convertChatCompletionToModelResponse pure — instead of threading req through it, set resp.Request = req in generateStream after the call, mirroring what generateComplete already does. That avoids changing the converter's signature and keeps a single pattern for both paths.
2. Delete the commented-out // Request: &ai.ModelRequest{}, line rather than leaving it in.
3. With the above, the existing resp.Request = req in generateComplete stays correct. As written, it's now redundant with the assignment inside the converter.
4. Add a regression test for the streaming path that asserts resp.Request.Messages (or resp.History()) preserves the input messages — TestGenerator_Stream currently discards the response with _, so this bug could silently return.

[apascal07]

Comments above.