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/lib/schemas/index.ts

@@ -1,3 +0,0 @@
-export * from "./common";
-export * from "./inbox";
-export * from "./insights";

src/shared/lib/types/index.ts

@@ -1,4 +0,0 @@
-export * from "./actions";
-export * from "./calendar";
-export * from "./notifications";
-export * from "./reports";