Viewer-agnostic model for extraction sources (the Retab /v1/extractions/{id}/sources shape): SourceAnchor union (pdf_bbox, image_bbox, spreadsheet/csv cell, docx/text span), Source, ExtractionSourcesResponse, and extractionSourcesToSourceMap to flatten the sources tree into a path-keyed SourceMap.
pnpm dlx shadcn@latest add "https://ui.retab.com/r/document-source.json"