feat(groq): support lc image types

[aarushi singh (aarushisingh04)]

pr description

• adds image input handling to ChatGroq in chat_models.py by converting langchain image content blocks into groq’s expected image_url message format.
• enables multimodal prompts (text + images) to be passed through the groq partner integration
• adds comprehensive unit test coverage for image formatting in test_chat_models.py

what does it solve?

removes the xfail from test_tool_message_histories_list_content in test_standard.py

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additional disclaimer : AI tools were used in assistance when forming and testing this change

[codspeed-hq]

Merging this PR will not alter performance

✅ 1 untouched benchmark
⏩ 33 skipped benchmarks¹

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_{Comparing aarushisingh04:feat/groq-image-input-support (19af613) with master (7c288f1)²}

Footnotes

1. 33 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 (4794f38) during the generation of this report, so 7c288f1 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩