refactor(nav): remover sidebar, unificar navegação na navbar

Componentes da sidebar lateral (app-sidebar, nav-main, nav-secondary,
nav-user, nav-link), sidebar.tsx e use-mobile.ts removidos.
Barrel exports órfãos de shared/hooks, shared/components/providers,
shared/lib/schemas e shared/lib/types também removidos.
Navbar recebe ajustes menores de markup e acessibilidade.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/shared/components/navigation/navbar/nav-pill.tsx

@@ -26,7 +26,7 @@ export function NavPill({ href, preservePeriod, children }: NavPillProps) {
 			className={cn(
 				buttonVariants({ variant: "navbar", size: "sm" }),
 				"capitalize",
-				isActive && "bg-black/15 text-black",
+				isActive && "bg-black/15 text-black dark:bg-white/15 dark:text-white",
 			)}
 		>
 			{children}