feat: add authentication modal component and user authentication logic

- Implemented AuthModal.vue for user login and registration with form handling.
- Created useAuth composable for managing user state and authentication requests.
- Added admin route middleware to protect admin routes.
- Developed admin login page with authentication checks.
- Implemented API endpoints for user management (login, logout, fetch user, register).
- Created database migrations for users table and updated movies table.
- Added utility functions for password hashing and JWT token management.

app/composables/useAuth.ts

@@ -0,0 +1,23 @@
+export function useAuth() {
+  const user = useState<any>('auth-user', () => null)
+  const loading = useState('auth-loading', () => true)
+
+  async function fetchUser() {
+    try {
+      loading.value = true
+      const data = await $fetch('/api/auth/me')
+      user.value = data
+    } catch {
+      user.value = null
+    } finally {
+      loading.value = false
+    }
+  }
+
+  async function logout() {
+    await $fetch('/api/auth/logout', { method: 'POST' })
+    user.value = null
+  }
+
+  return { user, loading, fetchUser, logout }
+}