Fix: Add support for object-json and object-tool modes in completion language model

[devin-ai-integration]

Fixes #43

This PR adds support for object-json and object-tool modes in the completion language model, which were previously throwing UnsupportedFunctionalityError. This is critical for models like Anthropic Claude that use structured outputs.

Changes:

• Implemented object-json mode by setting response_format: { type: 'json_object' }
• Implemented object-tool mode by setting tool_choice and tools configuration
• Added tests for both modes

Link to Devin run: https://app.devin.ai/sessions/d010b351a6cc4766a994478e861e880d
Requested by: Louis ([email protected])

[devin-ai-integration]

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[devin-ai-integration]

Closing due to inactivity for more than 7 days.