Description

verifyGatewayContainerRunning() calls .trim() on result.stdout, which is a Buffer, not a string. Crashes with TypeError when onboarding a second sandbox while a gateway is already running. First onboard succeeds, second crashes at preflight.

Regression from PR #2032.

Reproduction Steps

1. Run NEMOCLAW_SANDBOX_NAME=sandbox-a nemoclaw onboard --non-interactive (succeeds)
2. Run NEMOCLAW_SANDBOX_NAME=sandbox-b nemoclaw onboard --non-interactive (crashes at preflight)

Environment

• OS: Ubuntu 24.04 (GitHub Actions ubuntu-latest)
• Node.js: v22.22.2
• Docker: GitHub runner default
• NemoClaw: v0.1.0 (main branch, Apr 18 2026)
• OpenShell CLI: openshell 0.0.26

Debug Output

Not applicable — crash occurs before debug can run.

Logs

TypeError: (result.stdout || "").trim is not a function
    at verifyGatewayContainerRunning (onboard.js:106:54)
    at preflight (onboard.js:2068:32)
    at Object.onboard [as runOnboard] (onboard.js:5191:25)
    at async runOnboardCommand (onboard-command.js:82:5)
    at async onboard (nemoclaw.js:703:5)

Source: src/lib/onboard.ts line 141
  if (result.status === 0 && (result.stdout || "").trim() === "true") {

Fix: String(result.stdout || "").trim()
PR with fix: https://github.com/NVIDIA/NemoClaw/compare/main...TruongNguyenG:NemoClaw:fix/gateway-container-probe-buffer

Checklist

• I confirmed this bug is reproducible
• I searched existing issues and this is not a duplicate