Add automated Vercel-style llms.txt generation

[fcakyon]

Adds automatic Vercel-style llms.txt file generation after site build.

Generated file: llms.txt

ultralytics-mkdocs-llmstxt.mp4

🛠️ PR Summary

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🌟 Summary

Adds automatic generation of a Vercel-style llms.txt file after MkDocs builds complete. 🤖📄

📊 Key Changes

• Introduces a new plugin option add_llms_txt (default True) and hooks into on_post_build to generate llms.txt.
• Implements generate_llms_txt() in plugin/postprocess.py to create site/llms.txt from nav (preferred) or by scanning docs/**/*.md.
• Extracts optional page descriptions from Markdown frontmatter and includes them alongside links for richer LLM-friendly indexing.
• Extends standalone postprocess_site() to also generate llms.txt when add_llms_txt=True.

🎯 Purpose & Impact

• Improves LLM consumption of the docs by providing a single structured index of key pages and sections.
• Keeps llms.txt automatically in sync with the site navigation and build output, reducing manual maintenance.
• Enables consistent output both in-plugin (MkDocs build) and in standalone postprocessing flows.

[UltralyticsAssistant]

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[UltralyticsAssistant]

🔍 PR Review

_{Made with ❤️ by Ultralytics Actions}

Good addition overall: the feature is scoped, integrates cleanly via on_post_build, and the standalone flow is updated consistently. Main issues to address are correctness of nav traversal (top-level strings / single-page sections are currently skipped) and ensuring Path/path normalization is reliable at runtime. Minor note: avoid unconditional print() noise in build logs.

💬 Posted 4 inline comments