fix(cli): stop agents command from being unrecognized (#16267) (#16293)

Merged via /review-pr -> /prepare-pr -> /merge-pr.

Prepared head SHA: d7288f57fada313b3f474f28d9fc62075025ae81
Co-authored-by: yinghaosang <261132136+yinghaosang@users.noreply.github.com>
Co-authored-by: gumadeiras <5599352+gumadeiras@users.noreply.github.com>
Reviewed-by: @gumadeiras

src/cli/program/command-registry.ts

@@ -78,7 +78,10 @@ const coreEntries: CoreCliEntry[] = [
     },
   },
   {
-    commands: [{ name: "agent", description: "Agent commands" }],
+    commands: [
+      { name: "agent", description: "Agent commands" },
+      { name: "agents", description: "Manage isolated agents" },
+    ],
     register: async ({ program, ctx }) => {
       const mod = await import("./register.agent.js");
       mod.registerAgentCommands(program, { agentChannelOptions: ctx.agentChannelOptions });