[BREAKING] Python: fix OpenAI Azure routing and provider samples (#4925)

* Python: fix OpenAI Azure routing and provider samples

Prefer OpenAI when OPENAI_API_KEY is present unless Azure is explicitly requested. Clarify constructor docs, keep deprecated Azure wrappers compatible with stricter settings validation, and refresh the provider samples and tests to use the current client patterns.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix bandit

* Python: align OpenAI embedding Azure routing

Extend the shared OpenAI-vs-Azure routing and credential behavior to the embedding client, add Azure embedding regression coverage, and refresh the embedding samples to use the generic client path.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: fix embedding client pyright check

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: thin OpenAI embedding wrapper

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: document embedding overload routing

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: fix callable OpenAI key routing

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: fix Azure credential routing tests

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: address OpenAI review feedback

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: narrow Azure routing markers

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: refine OpenAI model fallback order

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: narrow Azure deployment docs

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: remove embedding routing wording

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: run embedding Azure integration tests

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* changed variable name

* Python: expand OpenAI package README

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* clarified readme

* Python: fix Azure OpenAI integration setup

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: correct Azure integration env mapping

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* updated code to fix int tests

* test updates

* test fix

* fix test setup

* updates to tests and setup

* remove openai assistants int tests

* improvements in int tests

* fix env var

* fix env vars

* fix azure responses test

* trigger actions

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Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

python/samples/02-agents/middleware/README.md

@@ -25,7 +25,7 @@ The new usage tracking sample uses `OpenAIResponsesClient`, so set the usual Ope
 
 ```bash
 export OPENAI_API_KEY="your-openai-api-key"
-export OPENAI_RESPONSES_MODEL_ID="gpt-4.1-mini"
+export OPENAI_RESPONSES_MODEL="gpt-4.1-mini"
 ```
 
 Then run: