feat: add agent data detail modal with interface telemetry, conntrack flows, and raw payload viewer

Add ScrollText icon button to nodes table to open agent data modal, implement agentFlows/agentInterfaces/agentConntrack helpers to safely extract telemetry from last_payload with type guards, add Modal with status/flows/conntrack summary cards, display interface list with operstate/vmid/rx/tx stats in scrollable container, show top 50 conntrack flows with source/destination/protocol/bytes/packets/state details

frontend/src/pages/Nodes.tsx

@@ -1,5 +1,5 @@
 import { useMutation, useQuery } from "@tanstack/react-query";
-import { Cpu, Copy, RadioTower } from "lucide-react";
+import { Activity, Cpu, Copy, RadioTower, ScrollText } from "lucide-react";
 import { useState } from "react";
 
 import { AgentInstallInfo, api, Node } from "../api/client";
@@ -11,6 +11,7 @@ import { PageHeader } from "../components/PageHeader";
 export function Nodes() {
   const nodes = useQuery({ queryKey: ["nodes-agents"], queryFn: () => api<Node[]>("/nodes/agents") });
   const [selectedNode, setSelectedNode] = useState<Node | null>(null);
+  const [detailNode, setDetailNode] = useState<Node | null>(null);
   const [copied, setCopied] = useState(false);
   const installInfo = useMutation({
     mutationFn: (node: Node) => api<AgentInstallInfo>(`/nodes/${node.id}/agent/install-info`),
@@ -28,6 +29,21 @@ export function Nodes() {
     setCopied(true);
   }
 
+  function agentFlows(node: Node) {
+    const flows = node.agent?.last_payload?.flows;
+    return Array.isArray(flows) ? flows : [];
+  }
+
+  function agentInterfaces(node: Node) {
+    const interfaces = node.agent?.last_payload?.interfaces;
+    return Array.isArray(interfaces) ? interfaces : [];
+  }
+
+  function agentConntrack(node: Node) {
+    const conntrack = node.agent?.last_payload?.conntrack;
+    return conntrack && typeof conntrack === "object" ? conntrack as Record<string, unknown> : {};
+  }
+
   return (
     <>
       <PageHeader title="Nodes" subtitle="Cluster nodes, capacity, health, and NexaFabric agent enrollment." />
@@ -56,6 +72,15 @@ export function Nodes() {
                 const node = row as unknown as Node;
                 return (
                   <div className="flex justify-end gap-2">
+                    <button
+                      className={iconButtonClass}
+                      title="View agent data"
+                      aria-label={`View agent data for ${node.name}`}
+                      disabled={!node.agent?.last_payload}
+                      onClick={() => setDetailNode(node)}
+                    >
+                      <ScrollText size={16} />
+                    </button>
                     <button
                       className={iconButtonClass}
                       title="Install node agent"
@@ -93,6 +118,70 @@ export function Nodes() {
           </button>
         </div>
       </Modal>
+      <Modal title="Agent Data" open={Boolean(detailNode)} onClose={() => setDetailNode(null)}>
+        {detailNode ? (
+          <div className="space-y-4">
+            <div className="flex items-center gap-2 font-medium">
+              <Activity size={18} />
+              {detailNode.name}
+            </div>
+            <div className="grid gap-3 sm:grid-cols-3">
+              <div className="rounded-md border border-border bg-canvas p-3">
+                <div className="text-xs text-slate-500 dark:text-slate-400">Status</div>
+                <div className="mt-1 text-sm font-medium">{detailNode.agent?.status ?? "not_installed"}</div>
+              </div>
+              <div className="rounded-md border border-border bg-canvas p-3">
+                <div className="text-xs text-slate-500 dark:text-slate-400">Flows</div>
+                <div className="mt-1 text-sm font-medium">{agentFlows(detailNode).length}</div>
+              </div>
+              <div className="rounded-md border border-border bg-canvas p-3">
+                <div className="text-xs text-slate-500 dark:text-slate-400">Conntrack</div>
+                <div className="mt-1 text-sm font-medium">{String(agentConntrack(detailNode).count ?? "unknown")}</div>
+              </div>
+            </div>
+            <section>
+              <div className="mb-2 text-sm font-medium">Interfaces</div>
+              <div className="max-h-48 overflow-auto rounded-md border border-border">
+                {agentInterfaces(detailNode).length ? agentInterfaces(detailNode).map((item, index) => {
+                  const iface = item as Record<string, unknown>;
+                  return (
+                    <div key={`${String(iface.name)}-${index}`} className="grid grid-cols-[1fr_auto] gap-3 border-b border-border px-3 py-2 text-xs last:border-0">
+                      <div>
+                        <div className="font-medium">{String(iface.name)}</div>
+                        <div className="text-slate-500">state {String(iface.operstate ?? "unknown")} {iface.vmid ? `· VMID ${String(iface.vmid)}` : ""}</div>
+                      </div>
+                      <div className="text-right text-slate-500">
+                        <div>rx {String(iface.rx_bytes ?? 0)}</div>
+                        <div>tx {String(iface.tx_bytes ?? 0)}</div>
+                      </div>
+                    </div>
+                  );
+                }) : <div className="p-3 text-xs text-slate-500">No interface telemetry in the last heartbeat.</div>}
+              </div>
+            </section>
+            <section>
+              <div className="mb-2 text-sm font-medium">Flows</div>
+              <div className="max-h-48 overflow-auto rounded-md border border-border">
+                {agentFlows(detailNode).length ? agentFlows(detailNode).slice(0, 50).map((item, index) => {
+                  const flow = item as Record<string, unknown>;
+                  return (
+                    <div key={index} className="border-b border-border px-3 py-2 text-xs last:border-0">
+                      <div className="font-medium">{String(flow.source_ip)}:{String(flow.source_port ?? "")} -> {String(flow.destination_ip)}:{String(flow.destination_port ?? "")}</div>
+                      <div className="text-slate-500">{String(flow.protocol ?? "unknown")} · {String(flow.bytes ?? 0)} bytes · {String(flow.packets ?? 0)} packets · {String(flow.state ?? "unknown")}</div>
+                    </div>
+                  );
+                }) : <div className="p-3 text-xs text-slate-500">No conntrack flows were reported in the last heartbeat.</div>}
+              </div>
+            </section>
+            <section>
+              <div className="mb-2 text-sm font-medium">Raw Payload</div>
+              <pre className="max-h-60 overflow-auto rounded-md border border-border bg-canvas p-3 text-xs">
+                {JSON.stringify(detailNode.agent?.last_payload ?? {}, null, 2)}
+              </pre>
+            </section>
+          </div>
+        ) : null}
+      </Modal>
     </>
   );
 }