Layers: one owner puts orbitals above the ship plane and floaters below; per-hull GridOffset is deleted

GameplaySettings carries ShipLayerHeight 3, OrbitalLayerHeight 15, FloaterLayerHeight 0 (authored in Settings.asset).
Entity.LayerHeight (Ship, OrbitalEntity) is the one offset RideHeight adds; DrawAhead.FloaterHeight is the floater
height ItemPickup and MineInstance draw at. HullData.GridOffset (Key 26) and the pickup/mine/prefab GridOffset fields
are gone with every reader. Fixtures (DrawnPose, FireControl*, ImpactFeedback) take heights from the layer owner;
LayerTests pin each kind's layer. FloatingItemsDrawnSmoke follows. ItemPickup/MineInstance.Bind take the settings from
ZoneRenderer. Builds as one commit with its tests; not compile-verified until the cut's head run.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Assets/Scripts/ServerShared/Settings.cs

@@ -278,6 +278,13 @@ public class GameplaySettings
     // normal is this times the speed at which it closed. 0 is perfectly inelastic, 1 perfectly elastic.
     public float ContactRestitution = .5f;
 
+    // Heights above the field of the ship plane, the orbital layer (stations, turrets: every OrbitalEntity) and the floater
+    // layer (loot, mines): orbitals above ships and floaters below them, so no ship ever touches either (ruling
+    // aetheria-gravity:orbitals-above-floaters-below).
+    public float ShipLayerHeight = 3f;
+    public float OrbitalLayerHeight = 15f;
+    public float FloaterLayerHeight = 0f;
+
     // The floor an AI's own predicted hit probability (FireControl.HitProbability) must clear before it counts
     // a firing solution worth taking (Combat.cs, TurretController.cs). Player fire is gated on arc alone
     // (Weapon.ArcAllowsFire, Q2) -- this threshold is an AI fire-discipline heuristic, not part of the roll.