- Replace the sparse disk (radius, flatten, spiral arms, per-type radiusBand)
with a seeded square domain placed by Bridson Poisson-disk sampling for
even, organic star spacing (no clumps/voids).
- Add a home→far difficulty axis: each record now carries `d` (0 at the home
corner, 1 at the opposite corner) and a named zone; type distribution is
mixed per zone via `distribution.zoneMix` instead of radial bands.
- Move the starting system to the star nearest the configured corner
(`startingSystem.policy: "corner"`, default SE / lower right), with
`center` and `random` policies still supported.
- Increase default system count from 60 to 90 and retune settlement density
gradient, landing video slots, and test expectations to the new layout.
Brian Fertig
5e4f94f385