feat: Add API route to proxy payments wallet challenge requests to the backend.

frontend/app/api/payments/wallets/challenge/route.ts

@@ -16,19 +16,29 @@ export async function POST(req: NextRequest) {
   try {
     const body = await req.json();
     const auth = await buildBackendRequestHeaders(req);
+    const proxiedHeaders = new Headers(auth.headers);
+    proxiedHeaders.set("Content-Type", "application/json");
     const res = await fetch(`${API_BASE}/api/payments/wallets/challenge`, {
       method: "POST",
-      headers: {
-        ...auth.headers,
-        "Content-Type": "application/json",
-      },
+      headers: proxiedHeaders,
       body: JSON.stringify(body ?? {}),
       cache: "no-store",
     });
     if (!res.ok) {
       const raw = await res.text();
       const response = NextResponse.json(
-        { error: `Backend returned ${res.status}`, detail: raw.slice(0, 350) },
+        {
+          error: `Backend returned ${res.status}`,
+          detail: raw.slice(0, 350),
+          proxy_debug: {
+            has_authorization: proxiedHeaders.has("authorization"),
+            has_entitlement: proxiedHeaders.has("x-polyweather-entitlement"),
+            has_forwarded_user_id: proxiedHeaders.has(
+              "x-polyweather-auth-user-id",
+            ),
+            has_forwarded_email: proxiedHeaders.has("x-polyweather-auth-email"),
+          },
+        },
         { status: res.status },
       );
       return applyAuthResponseCookies(response, auth.response);