Placeholder: `scaffold` subcommand for the bunx CLI

[diegohb]

What to build (placeholder)

An interactive scaffold subcommand for opencode-architect's own CLI: it asks the developer basic questions about their intended plugin package (name, what it will ship — skills, commands, tools, agents, …) and deploys a new directory with the bundled templates applied, ready to add their extensions.

Not yet specified — this ticket is a placeholder. It needs its own grilling/spec pass before implementation: the question set, template selection by intended content, output directory layout, and how scaffolding interacts with the content declaration.

Acceptance criteria (placeholder)

• Spec drafted via a grilling session (question set, template mapping, output layout)
• This ticket updated with real acceptance criteria and moved to ready-for-agent

Blocked by

None (spec work can start immediately; implementation waits for the spec).