feat: widen openai dependency to support 2.x for litellm compatibility

[BV-Venky]

Description

Users who need LiteLLM > 1.80.10 (e.g, for SAP Generative AI Hub support) cannot install strands-agents[litellm] because LiteLLM's core dependency to use SAP models requires openai>=2.8.0, while strands has openai<1.110.0 for the litellm extra and openai<2.0.0 for the openai/sagemaker extras.

This widens the openai version upper bound in three optional dependency groups:

• litellm: openai>=1.68.0,<1.110.0 → openai>=1.68.0,<3.0.0
• openai: openai>=1.68.0,<2.0.0 → openai>=1.68.0,<3.0.0
• sagemaker: openai>=1.68.0,<2.0.0 → openai>=1.68.0,<3.0.0

The only breaking change in openai 2.0 (ResponseFunctionToolCallOutputItem.output type change) affects the Responses API, which strands does not use. All existing unit tests pass with openai 2.24.0.

Related Issues

Resolves #1672

Type of Change

New feature

Testing

• Installed openai 2.24.0 in hatch test environment

• All 2000 unit tests pass with openai 2.24.0

• Verified LiteLLMModel instantiation works with openai 2.24.0 present

• Reviewed openai CHANGELOG from 1.109.0 to 2.24.0; the only breaking change (ResponseFunctionToolCallOutputItem.output type) does not affect strands (uses Chat Completions API, not Responses API)

• I ran hatch run prepare

Checklist

• I have read the CONTRIBUTING document
• I have added any necessary tests that prove my fix is effective or my feature works
• I have updated the documentation accordingly
• I have added an appropriate example to the documentation to outline the feature, or no new docs are needed
• My changes generate no new warnings
• Any dependent changes have been merged and published

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