Add MWP readiness audit and first-use guidance

[sigilabcodex]

This PR audits the first-use MWP path and adds small operator-facing guidance for the core workflow.

Highlights:

• Adds docs/mwp-readiness-audit.md
• Adds first-deploy workflow guidance on the operator home page
• Improves empty states for orders, production, and handoff
• Surfaces runtime/demo visibility in the operator loop

Checks:

• npm run typecheck passed
• npm run build passed

This is a small MWP readiness stabilization pass, not a feature expansion.