fix(auth): resolve middleware Edge Runtime + layout redirect loop

Two bugs:
1. auth.ts imported postgres (Node.js TCP) which crashes in Edge Runtime,
   causing Auth.js to silently fall back to redirecting all requests to login.
   Fix: split into auth.config.ts (Edge-safe, no DB) used by middleware,
   and auth.ts (full, with DB) used by server components.

2. /agent/layout.tsx applied to /agent/login, so unauthenticated login page
   visits redirected to themselves in an infinite loop.
   Fix: moved dashboard + layout into (protected) route group so login page
   has no auth layout.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

teressa-copeland-homes/middleware.ts

@@ -1,25 +1,9 @@
-import { auth } from "@/lib/auth";
-import { NextResponse } from "next/server";
+import NextAuth from "next-auth";
+import { authConfig } from "@/lib/auth.config";
 
-export default auth((req) => {
-  const isLoggedIn = !!req.auth;
-  const isAgentRoute = req.nextUrl.pathname.startsWith("/agent");
-  const isLoginPage = req.nextUrl.pathname === "/agent/login";
-
-  // Protect all /agent/* routes except the login page itself
-  if (isAgentRoute && !isLoginPage && !isLoggedIn) {
-    return NextResponse.redirect(new URL("/agent/login", req.nextUrl.origin));
-  }
-
-  // Redirect already-authenticated users away from the login page
-  if (isLoginPage && isLoggedIn) {
-    return NextResponse.redirect(new URL("/agent/dashboard", req.nextUrl.origin));
-  }
-});
+const { auth } = NextAuth(authConfig);
+export default auth;
 
 export const config = {
-  matcher: [
-    // Run on /agent/* routes, excluding Next.js internals and static files
-    "/((?!_next/static|_next/image|favicon.ico).*)",
-  ],
+  matcher: ["/agent/:path*"],
 };