Request fix

- Auth.js handlers require NextRequest.
- The wrapper accepted plain Request.
Changed both GET and POST handlers to accept NextRequest.

src/__tests__/manager-auth-route.test.ts

@@ -1,4 +1,5 @@
 import { afterEach, describe, expect, it, vi } from "vitest";
+import { NextRequest } from "next/server";
 
 // The Manager must not load the business Auth.js module even if a stale
 // client requests `/api/auth/session`.
@@ -19,7 +20,7 @@ describe("Manager business-auth boundary", () => {
   it("returns 404 without importing business Auth.js", async () => {
     process.env.MANAGER_MODE = "true";
 
-    const response = await GET(new Request("https://manager.example.com/api/auth/session"));
+    const response = await GET(new NextRequest("https://manager.example.com/api/auth/session"));
 
     expect(response.status).toBe(404);
   });