Draw the electrical diagram (schéma unifilaire / multifilaire). kind: 'single-line' or 'multi-line'; view: a view id of the document (e.g. a wire-marking view). format 'svg' returns the SVG text of every sheet (or of 'sheet', numbered from 1); 'pdf' writes to 'path' if given, else returns base64 (requires the uniwire[pdf] extra); on the hosted server it returns pdf_url instead. To give the user the PDF, give them pdf_url as a clickable link. color: 'none' | 'conductors' | 'phase' | 'source' | 'status' | 'voltage' (adds a legend); conductor_colors: 'iec' (IEC 60445) | 'us'.