Add dashboard navigation and request timeouts

Added 'Back to Dashboard' buttons to all admin dashboard pages for improved navigation. Introduced AbortSignal timeouts to API client and middleware requests to prevent hanging network calls. Also enabled messaging customers from the order details page if Telegram info is available.

app/dashboard/orders/[id]/page.tsx

@@ -22,7 +22,8 @@ import {
   CardHeader,
   CardTitle,
 } from "@/components/ui/card";
-import { Clipboard, Truck, Package, ArrowRight, ChevronDown, AlertTriangle, Copy, Loader2, RefreshCw } from "lucide-react";
+import { Clipboard, Truck, Package, ArrowRight, ChevronDown, AlertTriangle, Copy, Loader2, RefreshCw, MessageCircle } from "lucide-react";
+import Link from "next/link";
 import { useRouter } from "next/navigation";
 import { toast } from "sonner";
 import {
@@ -829,6 +830,22 @@ export default function OrderDetailsPage() {
                         </div>
                       )}
                     </div>
+                    {(order?.telegramBuyerId || order?.telegramUsername) && (
+                      <div className="pt-2">
+                        <Button
+                          variant="secondary"
+                          size="sm"
+                          asChild
+                        >
+                          <Link href={`/dashboard/chats/new?buyerId=${order?.telegramBuyerId || order?.telegramUsername}`}
+                            title={`Chat with customer${order?.telegramUsername ? ` @${order.telegramUsername}` : ''}`}
+                          >
+                            <MessageCircle className="h-4 w-4 mr-2" />
+                            Message customer
+                          </Link>
+                        </Button>
+                      </div>
+                    )}
                   </div>
                 )}