- increase grid columns across breakpoints including md, 2xl, and custom 16-col
- add aspect-square and justify-center to icon cards for uniform sizing
- update card style with solid border and background instead of transparent hover-only
- enlarge icon size from w-5/h-5 to w-7/h-7 and set color to white
- add full-width and padding to icon label for better text containment
- add `ZEN_DEVKIT` env variable to enable/disable devkit
- add `isDevkitEnabled()` utility and export it from public api
- register devkit nav section and items conditionally when devkit is enabled
- add devkit route handling in admin page client and server
- add DevkitPage, ComponentsPage, and IconsPage client components
hykocx