feat(openai): support apply_patch built-in tool

[Nidhi Rajani (nidhi1603)]

Fixes #37031

Adds support for OpenAI Responses API apply_patch built-in tool.

This PR:

• Adds apply_patch to the OpenAI well-known tools list.
• Adds apply_patch to LangChain Core's OpenAI built-in tool passthrough list so bind_tools([{"type": "apply_patch"}]) works.
• Preserves apply_patch_call and apply_patch_call_output items when converting OpenAI Responses API outputs into LangChain AIMessage.content.
• Preserves the same item types in streaming AIMessageChunk conversion.
• Supports round-trip input conversion for apply_patch_call and apply_patch_call_output.
• Adds unit tests for core tool passthrough, non-streaming conversion, streaming conversion, and round-trip input conversion.

Testing

• cd libs/core && uv run --group test pytest tests/unit_tests/utils/test_function_calling.py -k "apply_patch" -vv
• cd libs/partners/openai && uv run --group test pytest tests/unit_tests/chat_models/test_base.py -k "apply_patch" -vv
• cd libs/core && uv run --all-groups ruff check langchain_core/utils/function_calling.py tests/unit_tests/utils/test_function_calling.py
• cd libs/partners/openai && uv run --all-groups ruff check langchain_openai/chat_models/base.py tests/unit_tests/chat_models/test_base.py

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[codspeed-hq]

Merging this PR will not alter performance

✅ 13 untouched benchmarks
⏩ 2 skipped benchmarks¹

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_{Comparing nidhi1603:feat/openai-apply-patch-tool (3a34a22) with master (8eb3bec)²}

Footnotes

1. 2 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

2. No successful run was found on master (e411a4e) during the generation of this report, so 8eb3bec was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩