미들웨어 인증 처리

// middleware.ts
import { createMiddlewareClient } from '@supabase/ssr'
import { NextResponse } from 'next/server'

export async function middleware(request) {
  const response = NextResponse.next()
  const supabase = createServerClient(url, key, {
    cookies: { /* get/set/delete from request/response */ }
  })

  // 세션 갱신 (중요!)
  await supabase.auth.getSession()

  // 보호된 경로 처리
  const { data: { user } } = await supabase.auth.getUser()
  if (!user && request.nextUrl.pathname.startsWith('/dashboard')) {
    return NextResponse.redirect(new URL('/login', request.url))
  }
  return response
}