Buildkite: fetch SSH keys from Vault at step start

[reakaleek]

What

• Fetch elasticmachine SSH keys from Vault in the Buildkite pre-command hook for docs PR and docs build pipelines
• Remove mid-script Vault reads from the build scripts

Why

• Buildkite job Vault tokens expire after about 10–20 minutes
• Docs PR builds can run longer than that, especially when product repo setup runs before the build
• Late Vault access can fail with an expired token error

Notes

• SSH keys stay on disk with chmod 600, not in environment variables
• ssh-keyscan and ssh-agent behavior in the build scripts is unchanged

Made with Cursor

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