UX mockups

Throwaway HTML+JS experiments, served static by inlet at mockups.listing.network. Edit a file, refresh — no build, no restart. Not part of the platform site-serve path.

Reference (moved from platform/mockups)

• DESIGN-RATIONALE.md
• PUBLIC-LISTINGS.md
• Listings Management — Admin.pdf

New experiment: drop <name>/index.html in this dir and add a line to the experiments list below (or just navigate straight to it).