Remove MCP server references from documentation

[devin-ai-integration]

Summary

Removes all references to MCP (Model Context Protocol) server support from the Fern documentation. This includes:

• Deleted the MCP server documentation page (fern/products/docs/pages/ai/mcp-server.mdx)
• Removed the MCP server entry from the AI features navigation
• Updated redirects to point old MCP server URLs to the AI features overview page
• Removed MCP server mentions from the AI features overview, getting started page, changelog, and Stainless comparison page

Updates since last revision

• Added <CardGroup cols={2}> wrapper around the llms.txt card in the AI features overview page to maintain consistent card width styling

Review & Testing Checklist for Human

• Verify the redirect from /learn/docs/ai-features/mcp-server to /learn/docs/ai-features/overview works correctly on the preview deployment
• Check that no broken links remain by reviewing the preview site's AI features section
• Confirm the Stainless comparison page still reads coherently after removing MCP server rows from the comparison tables
• Verify the llms.txt card in the "Optimize for AI" section displays at half-width (not full-width)
• Consider whether the orphaned MCP server images (mcp-server-light.png, mcp-server-dark.png) in getting-started/images/ should also be deleted

Recommended test plan: Navigate through the AI features section on the preview deployment, click through all links, and verify the redirects work for any bookmarked MCP server URLs.

Notes

• The fern check command passed for docs-yml configuration
• Existing redirects for /learn/docs/ai/mcp-server and /learn/docs/ai-features/mcp-server/overview were updated to point to the overview page

Link to Devin run: https://app.devin.ai/sessions/3585d28789104a21bf371cded4ce1c85
Requested by: Fern Support

[devin-ai-integration]

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[github-actions]

🌿 Preview your docs: https://fern-preview-2c3170f4-fe8b-4f0a-977d-e61ad7347d68.docs.buildwithfern.com/learn

[github-actions]

🌿 Preview your docs: https://fern-preview-9fd89788-838e-4768-bc57-8fb979b2d3ce.docs.buildwithfern.com/learn