Summary

Implement a first-class diagnostics command that helps users quickly verify whether their environment is ready for specific document types before running partitioning.

Today, users typically discover missing dependencies only after a runtime failure (or by manually running scripts/collect_env.py). This creates friction, especially with optional extras and system-level dependencies across platforms.

Proposed feature

Add a CLI command such as:

• unstructured doctor
• unstructured doctor --for pdf
• unstructured doctor --file path/to/document.pdf

Expected behavior

• Report Python/package/system dependency status in a readable table.
• Show supported file types in the current environment.
• For unsupported file types, provide actionable install hints (e.g. pip install "unstructured[pdf]").
• Include platform-aware checks (Windows/macOS/Linux) for common system requirements (e.g. libmagic, tesseract, libreoffice where relevant).
• Return non-zero exit code when requested capability is not available (useful for CI).

Why this matters

• Reduces setup confusion and support load.
• Improves onboarding and developer experience.
• Gives users proactive guidance instead of reactive runtime errors.