feat: add navigation-menu (#31)

* feat: navigation-menu

* fix: export at the end

* fix: rounded-md

* fix: demo design

* rename: NavigationMenuRoot -> NavigationMenu

* feat: update roadmap

* feat: update style for navigation menu

* feat: implement navigation menu component

* feat: implement navigation menu for www

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Co-authored-by: shadcn <m@shadcn.com>

README.md

@@ -13,7 +13,7 @@ Beautifully designed components built with Radix UI and Tailwind CSS.
 - [ ] Toggle
 - [ ] Toggle Group
 - [ ] Toolbar
-- [ ] Navigation Menu
+- [ ] Navigation Menu (Vertical and Submenus)
 - [ ] Figma?
 
 ## Get Started