Moved docs/asset-engine/design-brief.md → docs/archive/asset-engine/design-brief.md
with a 12-line archival header pointing at the live implementation
artifacts (vh/asset-engine source, stacks/asset-engine/ deploy,
CATALOG-CONTRACT.md, services.yaml).
The brief explicitly framed itself as a pre-implementation handoff
("Hand this to a design agent before any pixels"). Implementation
shipped 2026-05-12; the brief's role is past. Kept for the design
rationale it carries (why Asset is first-class, why v1 is synchronous,
v2/v3 seam reasoning) — future contributors benefit from finding it
when wondering "why is it this way."
Surfaced by /tend-docs audit 2026-05-14.
vh
54d1e7137e