docs: document include prop for Schema component

[devin-ai-integration]

Summary

Documents the new include prop on the <Schema> component, added in fern-api/fern-platform#7267. Changes are limited to schema.mdx:

• Adds a Filtering fields subsection under Usage with code examples for include and exclude
• Adds a <ParamField> entry for include (placed before the existing exclude entry)
• Documents the interaction when both include and exclude are specified

Local testing

Verified the page renders correctly via fern docs dev on localhost:3000. The new "Filtering fields" subsection and include <ParamField> display as expected. All CI checks (vale, run, check-assignee) pass.

View original video (rec-912dec7b5e4d402f952e8634e400a341-edited.mp4)

Review & Testing Checklist for Human

• Verify example field names: The code examples use model and provider as field names on AIChatConfig. These were not validated against the actual type definition — swap to real field names if they are incorrect.
• Confirm include + exclude interaction: The docs state a field must be in the include list and not in the exclude list. Confirm this matches the actual implementation in fern-platform#7267.
• Check rendered page on preview deployment: Navigate to the Schema component page and ensure the new subsection and <ParamField> display correctly.

Suggested test plan: Open the deployed preview, navigate to the Schema component page (/learn/docs/writing-content/components/schema), and confirm the "Filtering fields" section and include property reference render correctly with no layout issues.

Notes

Link to Devin run | Requested by: Fern Support

[devin-ai-integration]

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🌿 Preview your docs: https://fern-preview-c34980a7-e5e4-47c5-a073-b4f17262dc41.docs.buildwithfern.com/learn

Here are the markdown pages you've updated:

• learn/docs/writing-content/components/schema