Add concealment meter and skinned collider baker; reorganize assets

- ConcealmentMeter: standalone component measuring the percentage of the
  character volume embedded inside environment geometry (bake -> voxelize via
  column ray-stabbing parity -> classify interior voxels against box/sphere/
  capsule/convex colliders and terrain). Always-on, throttled, gizmo debug.
- SkinnedColliderBaker: sole per-frame collider bake owner for skinned rigs.
  MeshPainter now delegates baking and only borrows BakedMesh for the GPU
  raster and cache refresh, so the collider stays fresh outside paint mode.
- Move pose assets to Assets/Poses, retire unused Insect scripts to
  Assets/Unused, restore Paintman.controller; mode scripts and scene updated.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Assets/Scripts/GameModeManager.cs

@@ -22,8 +22,8 @@ public class GameModeManager : MonoBehaviour
     [Tooltip("Mesh painter. Empty = found automatically.")]
     public MeshPainter painter;
 
-    [Tooltip("Insect / surface-walk controller. Empty = found automatically.")]
-    public InsectController insect;
+    //[Tooltip("Insect / surface-walk controller. Empty = found automatically.")]
+    //public InsectController insect;
 
     [Header("Switching")]
     [Tooltip("Key that cycles to the next mode.")]
@@ -39,7 +39,7 @@ public class GameModeManager : MonoBehaviour
     public PlayerCharacterController Player => player;
     public ThirdPersonOrbitInput CameraInput => cameraInput;
     public MeshPainter Painter => painter;
-    public InsectController Insect => insect;
+    //public InsectController Insect => insect;
 
     /// <summary>Raised after a mode switch finishes (the new mode's Enter has already run).
     /// Argument = the now-active mode. Used by UI (e.g. the paint HUD) to follow the mode.</summary>
@@ -57,7 +57,7 @@ public class GameModeManager : MonoBehaviour
         if (!player) player = FindFirstObjectByType<PlayerCharacterController>();
         if (!cameraInput) cameraInput = FindFirstObjectByType<ThirdPersonOrbitInput>();
         if (!painter) painter = FindFirstObjectByType<MeshPainter>();
-        if (!insect) insect = FindFirstObjectByType<InsectController>();
+        //if (!insect) insect = FindFirstObjectByType<InsectController>();
 
         BuildModes();
     }
@@ -82,8 +82,8 @@ public class GameModeManager : MonoBehaviour
 
         // Insect mode only joins the Tab cycle when a surface walker is present, so a scene
         // without one behaves exactly as before (no dead, player-freezing mode in the cycle).
-        if (insect)
-            _modes.Add(new InsectMode());
+        //if (insect)
+        //    _modes.Add(new InsectMode());
 
         foreach (var m in _modes)
             m.Bind(this);