Add tab and approval flow for server -> client sampling

client/src/components/SamplingTab.tsx

@@ -0,0 +1,65 @@
+import { TabsContent } from "@/components/ui/tabs";
+import { Alert, AlertDescription } from "@/components/ui/alert";
+import { Button } from "@/components/ui/button";
+import {
+  CreateMessageRequest,
+  CreateMessageResult,
+} from "mcp-typescript/types.js";
+
+export type PendingRequest = {
+  id: number;
+  request: CreateMessageRequest;
+};
+
+export type Props = {
+  pendingRequests: PendingRequest[];
+  onApprove: (id: number, result: CreateMessageResult) => void;
+  onReject: (id: number) => void;
+};
+
+const SamplingTab = ({ pendingRequests, onApprove, onReject }: Props) => {
+  const handleApprove = (id: number) => {
+    // For now, just return a stub response
+    onApprove(id, {
+      model: "stub-model",
+      stopReason: "endTurn",
+      role: "assistant",
+      content: {
+        type: "text",
+        text: "This is a stub response.",
+      },
+    });
+  };
+
+  return (
+    <TabsContent value="sampling" className="h-96">
+      <Alert>
+        <AlertDescription>
+          When the server requests LLM sampling, requests will appear here for
+          approval.
+        </AlertDescription>
+      </Alert>
+      <div className="mt-4 space-y-4">
+        <h3 className="text-lg font-semibold">Recent Requests</h3>
+        {pendingRequests.map((request) => (
+          <div key={request.id} className="p-4 border rounded-lg space-y-4">
+            <pre className="bg-gray-50 p-2 rounded">
+              {JSON.stringify(request.request, null, 2)}
+            </pre>
+            <div className="flex space-x-2">
+              <Button onClick={() => handleApprove(request.id)}>Approve</Button>
+              <Button variant="outline" onClick={() => onReject(request.id)}>
+                Reject
+              </Button>
+            </div>
+          </div>
+        ))}
+        {pendingRequests.length === 0 && (
+          <p className="text-gray-500">No pending requests</p>
+        )}
+      </div>
+    </TabsContent>
+  );
+};
+
+export default SamplingTab;