docs: enhance SEO metadata documentation with best practices

[devin-ai-integration]

docs: enhance SEO metadata documentation with best practices

Summary

Enhanced the SEO metadata configuration page by replacing a single paragraph of general guidance with a structured "Best practices" section. The new section provides specific, actionable guidelines for configuring SEO metadata including:

• Character limits for titles (50-60) and descriptions (150-160)
• Image size recommendations (1200x630 pixels)
• Branding consistency guidance
• Links to testing tools (Facebook Sharing Debugger and Twitter Card Validator)

This improves the documentation by giving users concrete specifications rather than vague guidance like "keep descriptions between 150-160 characters" buried in a paragraph.

Review & Testing Checklist for Human

• Verify the two external links work (Facebook Sharing Debugger and Twitter Card Validator)
• Confirm the best practices align with current SEO/Open Graph standards
• Check that the tone and formatting match Fern's documentation style guidelines
• Preview the rendered page locally with fern docs dev to verify formatting

Notes

• This is a documentation-only change with no code modifications
• Best practices are based on well-established industry standards for Open Graph and Twitter Cards
• The existing content structure (page metadata and website metadata sections) remains unchanged

Session details:

• Requested by: danny@buildwithfern.com (@dannysheridan)
• Session URL: https://app.devin.ai/sessions/6f152d767e8e4d6aa28d737373aa47f9

[devin-ai-integration]

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