feat(proxy): add outbound HTTP proxy support for OAuth + provider requests

- Patch Node fetch via undici ProxyAgent when HTTP_PROXY/HTTPS_PROXY/ALL_PROXY is set
- Ensure proxy patch is loaded for both chat pipeline and OAuth token exchange
- Add Dashboard Settings → Network to edit outbound proxy and apply immediately
- Persist outbound proxy settings in local db and initialize on server startup
- Move proxy helpers to src/lib/network/ for better structure
- Rename src/proxy.js → src/dashboardGuard.js to avoid naming confusion
- Re-apply proxy env after DB import
- Fix: close old dispatcher on proxy URL change to prevent connection pool leak
- Fix: idempotency guard to avoid patching globalThis.fetch multiple times

Made-with: Cursor

src/dashboardGuard.js

@@ -0,0 +1,47 @@
+import { NextResponse } from "next/server";
+import { jwtVerify } from "jose";
+
+const SECRET = new TextEncoder().encode(
+  process.env.JWT_SECRET || "9router-default-secret-change-me"
+);
+
+export async function proxy(request) {
+  const { pathname } = request.nextUrl;
+
+  // Protect all dashboard routes
+  if (pathname.startsWith("/dashboard")) {
+    const token = request.cookies.get("auth_token")?.value;
+
+    if (token) {
+      try {
+        await jwtVerify(token, SECRET);
+        return NextResponse.next();
+      } catch (err) {
+        return NextResponse.redirect(new URL("/login", request.url));
+      }
+    }
+
+    const origin = request.nextUrl.origin;
+    try {
+      const res = await fetch(`${origin}/api/settings/require-login`);
+      const data = await res.json();
+      if (data.requireLogin === false) {
+        return NextResponse.next();
+      }
+    } catch (err) {
+      // On error, require login
+    }
+    return NextResponse.redirect(new URL("/login", request.url));
+  }
+
+  // Redirect / to /dashboard if logged in, or /dashboard if it's the root
+  if (pathname === "/") {
+    return NextResponse.redirect(new URL("/dashboard", request.url));
+  }
+
+  return NextResponse.next();
+}
+
+export const config = {
+  matcher: ["/", "/dashboard/:path*"],
+};