- hero-banner: 3D glassy shield + brand DB logos (Postgres/MongoDB/MySQL),
  visual SELECT ✓ / DROP ✗ flow demo
- layers-diagram: concentric defense-in-depth arcs with legitimate query
  flow through all 5 layers and DROP TABLE blocked at L1
- architecture-diagram: code-editor aesthetic, accurate module layout
  (server/tools/sql_guard/rate_limiter/audit + mongo subgroup), 8 DB
  targets with driver labels
- Delete old SVG versions
- Bump 0.4.1 -> 0.4.2