- ground-model.ts: read schema 2 terrain_grid (origin, step, nx, ny, z),
checked the same way as the stored project form; schema 1 is still read.
- view/terrain.ts: the grid as a mesh in pier-scene coordinates
(x = E − pivot E, z = −(N − pivot N), y = EL), same as the pier frame.
Cells with a missing corner are not drawn.
- scene.ts: draws the terrain in place of the 60 m plane when the model has a
grid; the camera fits the members, not the terrain.
Co-Authored-By: Claude Haiku 5.5 <noreply@anthropic.com>
