feat: integrate NextAuth.js for authentication, update database service to use better-sqlite3 adapter, and enhance header component with user session management

src/components/Providers.tsx

@@ -1,5 +1,6 @@
 'use client';
 
+import { SessionProvider } from 'next-auth/react';
 import { ThemeProvider } from '@/contexts/ThemeContext';
 import { Header } from '@/components/layout/Header';
 import { ReactNode } from 'react';
@@ -10,11 +11,13 @@ interface ProvidersProps {
 
 export function Providers({ children }: ProvidersProps) {
   return (
-    <ThemeProvider>
-      <div className="min-h-screen bg-background">
-        <Header />
-        {children}
-      </div>
-    </ThemeProvider>
+    <SessionProvider>
+      <ThemeProvider>
+        <div className="min-h-screen bg-background">
+          <Header />
+          {children}
+        </div>
+      </ThemeProvider>
+    </SessionProvider>
   );
 }