Add docs/env-sync-scripts.md; cross-link from deploy README, feature docs, README, and script headers. Co-authored-by: Cursor <cursoragent@cursor.com>
sync_four_exchange_position_sizing_env.py appends missing POSITION_SIZING_MODE and FULL_MARGIN_BUFFER_RATIO, optional --set-mode/--set-buffer; docs updated. Co-authored-by: Cursor <cursoragent@cursor.com>