feat: add json response format for siliconflow models

[orangeclk]

Checklist:

Important

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• Please open an issue before creating a PR or link to an existing issue
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
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Description

Describe the big picture of your changes here to communicate to the maintainers why we should accept this pull request. If it fixes a bug or resolves a feature request, be sure to link to that issue. Close issue syntax: Fixes #<issue number>, see documentation for more details.

Add json mode support for non-deprecated models on siliconflow.

Fixes #10656

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update, included: Dify Document
• Improvement, including but not limited to code refactoring, performance optimization, and UI/UX improvement
• Dependency upgrade

Testing Instructions

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• Test A
• Test B