Refactor authentication system: replace NextAuth with custom login/logout/session handling, improve cookie management, and enhance error handling

app/api/auth/logout/route.ts

@@ -0,0 +1,17 @@
+import { NextResponse } from "next/server"
+import { AUTH_COOKIE_NAME } from "@/lib/auth-cookie"
+
+export const runtime = "nodejs"
+export const dynamic = "force-dynamic"
+
+export async function POST() {
+  const response = NextResponse.json({ success: true }, { status: 200 })
+  response.cookies.set(AUTH_COOKIE_NAME, "", {
+    httpOnly: true,
+    secure: process.env.NODE_ENV === "production",
+    sameSite: "lax",
+    path: "/",
+    maxAge: 0,
+  })
+  return response
+}