Acquire and set up new build hardware

[turt2live]

• Acquire physical build hardware
• Invoke the retirement plan on the existing build hardware
• Set up VMs for Windows, Linux
• Set up buildkite agents on all 3 operating systems (macOS, Windows, Linux)
• Place hardware in safe.
• Acquire yubikeys.

[turt2live]

We'll track the required bits of this as new issues if needed. I think we've done most of the steps, and some of the steps aren't actionable in the modern world anyways.