Track a future Go/Cobra CLI demo

[codeforester]

Track a future advanced demo showing how Base should orchestrate a small Go/Cobra CLI once Base starts supporting Go-heavy projects such as Banyan Labs.

Acceptance criteria:

• Decide whether this belongs in base-demo or a separate base-demo-go repository.
• Keep Go out of the baseline demo unless it remains lightweight and clearly teaches Base orchestration.
• If implemented later, use Go's standard toolchain and Cobra for non-trivial CLI shape.
• Do not require Go for the current base-demo baseline.