Staging environments are live and fully operational. Marks the remaining
verification tasks complete, syncs the delta spec to main specs, and
archives the change.
Also adds a "When to Use Local vs. Staging" reference table to the
local-dev-environment spec so the boundary between the two environments
is documented in one place.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
