fix: ignore stale workbench active trace

internal/cloud/server-code-agent-http.ts

@@ -902,7 +902,17 @@ async function claimWorkbenchWorkspaceTurn({ params = {}, options = {}, traceId,
   }
   const activeTraceId = safeTraceId(workspace.activeTraceId);
   const activeResult = activeTraceId ? await resolveWorkbenchActiveTraceResult(activeTraceId, options) : null;
-  if (activeTraceId && (!activeResult || activeResult.status === "running")) {
+  const selectedConversationId = safeConversationId(workspace.selectedConversationId);
+  const shouldInspectSelectedConversation = Boolean(
+    activeTraceId && !activeResult && selectedConversationId && options.accessController?.visibleConversationForActor
+  );
+  const selectedConversation = shouldInspectSelectedConversation
+    ? await options.accessController.visibleConversationForActor(options.actor, selectedConversationId, workspace.projectId)
+    : null;
+  const activeTraceBlocksTurn = Boolean(
+    activeTraceId && (activeResult?.status === "running" || (!activeResult && isActiveWorkbenchConversation(selectedConversation)))
+  );
+  if (activeTraceBlocksTurn) {
     sendJson(response, 409, {
       ok: false,
       status: "workspace_agent_busy",
@@ -941,6 +951,15 @@ async function claimWorkbenchWorkspaceTurn({ params = {}, options = {}, traceId,
   return { workspace: updated ?? workspace };
 }
 
+function isActiveWorkbenchConversation(conversation = null) {
+  if (!conversation) return false;
+  const values = [conversation.status, conversation.session?.status, conversation.snapshot?.sessionStatus];
+  for (const message of Array.isArray(conversation.messages) ? conversation.messages.slice(-5) : []) {
+    values.push(message?.status, message?.runnerTrace?.sessionStatus, message?.sessionStatus);
+  }
+  return values.some((value) => ["running", "busy", "pending", "active", "queued"].includes(textValue(value).toLowerCase()));
+}
+
 async function resolveWorkbenchActiveTraceResult(traceId, options = {}) {
   if (!safeTraceId(traceId)) return null;
   const cached = options.codeAgentChatResults?.get?.(traceId) ?? null;