feat(layout): add mobile sidebar drawer navigation

src/App.tsx

@@ -1,4 +1,5 @@
 import { createBrowserRouter, RouterProvider, Navigate, Outlet } from "react-router-dom"
+import { useState } from "react"
 import { ThemeProvider } from "./components/ThemeProvider"
 import { LanguageProvider } from "./components/LanguageProvider"
 import { Toaster } from "./components/ui/toaster"
@@ -21,12 +22,17 @@ import Tags from "./pages/Tags"
 import Timesheet from "./pages/Timesheet"
 
 const MainLayout = () => {
+  const [mobileSidebarOpen, setMobileSidebarOpen] = useState(false)
+
   return (
     <div className="flex h-screen bg-slate-50 dark:bg-slate-950 overflow-hidden text-slate-900 dark:text-slate-100">
-      <Sidebar />
+      <Sidebar
+        mobileOpen={mobileSidebarOpen}
+        onMobileClose={() => setMobileSidebarOpen(false)}
+      />
 
       <div className="flex-1 flex flex-col h-screen overflow-y-auto relative">
-        <Navbar />
+        <Navbar onOpenSidebar={() => setMobileSidebarOpen(true)} />
 
         <main className="flex-1 relative">
           <Outlet />