chore: upgrade Node.js to 22.22.0 for security fix

[devin-ai-integration]

Description

Upgrades the Node.js version in the sign-client Dockerfile from node:21-alpine to node:22.22.0-alpine to address a critical security vulnerability affecting virtually every production Node.js app.

Reference: https://x.com/matteocollina/status/2011137343323865196

Patched Node.js versions are: 20.20.0, 22.22.0, 24.13.0, 25.3.0. Node.js 21 is not in the patched versions list, so upgrading to 22.22.0 is required.

Type of change

• Chore (non-breaking change that addresses non-functional tasks, maintenance, or code quality improvements)

How has this been tested?

The Docker image tag node:22.22.0-alpine has been verified to exist on Docker Hub. Full testing should be performed by CI to ensure the Docker build succeeds with the new Node.js version.

Checklist

• I have performed a self-review of my own code
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules

Human Review Checklist

• Verify the Docker image builds successfully with Node.js 22.22.0
• Confirm there are no Node.js 21 → 22 breaking changes affecting this package
• Validate that canary tests pass with the updated image

Additional Information

• Link to Devin run: https://app.devin.ai/sessions/fe3816d19c9046e19f1c9a2ee5273c2d
• Requested by: Ben Kremer (@bkrem)

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