Add-on: PDF Preprocessing (Page Artifacts)

Use this skill to implement the preprocessing stage that turns an uploaded PDF into:

• page-level text/markdown artifacts (raw)
• page-level cleaned artifacts (after header/footer cleanup; separate stage)
• stable provenance metadata for audit + reprocessing

Inputs

Collect:

• PDF_PARSER: docling (if available) or pypdf/pdfplumber fallback.
• PAGE_MARKER_STYLE: structured-pages (preferred) or markdown-markers.

Output Contracts

For each page (1-based), persist:

• raw_page_markdown (or raw extracted text)
• metadata_jsonb including parser name/version and extraction params