LANTERN purge B2: delete EB-2 turret defense

TurretFireSystem, TurretAuthoring, Turret.prefab, Turret component, turret cap,
B hotkey, HUD Charge chip + out-of-ammo cue, catalog entry, Tuning consts, tests
(-7, 452 green). StructureType.Turret byte + ResourceId.Charge stay reserved.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Assets/_Project/Scripts/Client/UI/HudTheme.cs

@@ -48,12 +48,10 @@ namespace ProjectM.Client
         public Sprite BioIcon;
 
         [Header("Structure icons")]
-        public Sprite TurretIcon;
         public Sprite WallIcon;
         public Sprite PylonIcon;
 
         [Header("Build-ghost preview meshes (authored real-size, ground pivot — BuildSendSystem)")]
-        public Mesh TurretGhostMesh;
         public Mesh WallGhostMesh;
 
         [Header("Build-mode control glyphs")]
@@ -82,7 +80,6 @@ namespace ProjectM.Client
         {
             switch (type)
             {
-                case StructureType.Turret: return TurretIcon;
                 case StructureType.Wall: return WallIcon;
                 case StructureType.Pylon: return PylonIcon;
                 default: return null;
@@ -94,7 +91,6 @@ namespace ProjectM.Client
         {
             switch (type)
             {
-                case StructureType.Turret: return TurretGhostMesh;
                 case StructureType.Wall: return WallGhostMesh;
                 default: return null;
             }