v1.2

Editor layout reworked into three collapsible panels with responsive sizing. Artifacts support configurable data, Leaflet maps, alignment, and persistent resizing. Added DOCX/PDF/TXT ingestion into chat context, a stop button for streaming, and chat reset. Security hardening across artifact iframes, image downloads, and chat endpoints. Fixed markdown bleedthrough in outline, map tile loading, step badge visibility, and orphan module handling.