appsmith-statistics-app/docs/README.md

Navigation updates

• Added the Units Ordered nav button beneath Units Shipped on every Sales canvas so the new sales dashboard route is reachable from Capacity Planning, Units Ordered, and Units Shipped.
• Each page now hardcodes the appropriate nav button to appsmith.theme.colors.primaryColor and keeps the others at appsmith.theme.colors.backgroundColor, guaranteeing only the current canvas renders with the darker highlight without referencing appsmith.page.