Retained specialized and stable-link pages

These pages remain available for existing links or specialized reference. Start new work with the beginner path, workflow choice and the canonical pages in the navigation. Historical records keep their dated evidence boundaries.

• api/qa_plots.md
• dev/drone-bulk-contract-diagnostic-2026-09-29.md
• dev-notes.md
• documentation-overview.md
• pipeline.md
• pipeline/qa_panel.md
• qa.md
• refactor_notes.md

• usage/parquet_preview.md

• Notebook source and editing conventions