- Add levels 7-10 and move all 10 into campaign01 (campaign02 left empty
as scaffolding)
- Replace the old S-curve auto-layout with a 2-lane circuit: top lane
runs right→left, bottom lane left→right, finish flag in the
bottom-right corner. Comfortable up to ~12 levels per campaign.
- Re-export node/flag sprites as tight 512x512 badges (badge IS the
file) instead of centered-on-960x540 frames; update mapArt.js tables
(BADGE_FILE_FRAC, BADGE_HIT_FRAC, NODE_ART_FRAMES) and asset manifest
accordingly
- Size the finish-flag nudge to stay on-screen when a custom `positions`
layout ends at an edge (flips direction if out of bounds)
- Guard against empty campaigns: skip path/flag rendering when there are
no points, and bail early in _playFirst()
- Shrink node pill font slightly so the longest tag fits under tightly
spaced nodes
- Update README.md and sprites.md to reflect the new sprite convention,
lane geometry, and level count
