Function: buildLayeredInteractiveMesh()

function buildLayeredInteractiveMesh(
   sim, 
   levels, 
   variation, 
   options): LayeredInteractiveMesh;

Builds the sol interactive mesh for a rocky / metallic / gaseous body.

Parameters

Parameter	Type	Description
`sim`	`BodySimulation`	Pre-computed simulation (tiles, states, palette bridge).
`levels`	`TerrainLevel`[]	Palette driving vertex colours and per-tile sol heights.
`variation`	`BodyVariation`	Deterministic visual variation for the sol shader.
`options`	`LayeredInteractiveMeshOptions`	Per-body channels + optional tuning.