Refactor: extract shared helpers across scripts, trim remaining doc redundancy

Deduplication pass (44 extractions):
- New SmoothedLook: shared smoothed yaw/pitch look tick + view seeding
  (FirstPersonController, FreeCamController)
- New CharacterTeleport: disable-CC-around-teleport idiom (rescue,
  owner position apply, free-cam sync)
- New GeometryUtil: RescaleToUnitScale + TransformBounds (concealment
  meter/volume, skinned collider baker)
- Paint family: canonical map read/write shared between Net and
  Persistence, snapshot decode, backend stroke dispatch, RebuildBackend,
  ResolveSeed, chunked RPC send/gate/copy, CamoKnobs/HeightKnobs
  aggregates, SanitizeFileKey, NewMaskTexture, AdoptAlbedo, FindSlider
- Player/modes: GameMode SetPlayerControl/SetPainting/SetOrbitInputEnabled,
  InputUtil.GameplayKeyPressed, NearestClimbHit, ComputeXRay delegates to
  ComputeResolutionFreeze, FingerIK TryInPlaneAngle
- Match/misc: UnhookSessionCallbacks, SendEmptyNamedMessage, SwapScenes,
  RunSessionOpAsync, CovarianceEigen, CollectClusterPoints, MatchHud
  GUIStyle cache, HsvColorPicker rehook, VoxelCenter

Documentation pass: remove 6 triplicated doc blocks and 2 restating
inline comments left after the previous reduction.

Behavior-neutral; hot-path rasterizer loops intentionally untouched.

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

Assets/Scripts/ConcealmentMeter.cs

@@ -88,7 +88,6 @@ public class ConcealmentMeter : MonoBehaviour
     private readonly List<MeshCollider> _concave = new List<MeshCollider>();
     private readonly List<ConcealmentVolume> _volumes = new List<ConcealmentVolume>();
 
-    // Gizmo cache.
     private readonly List<Vector3> _gizPos = new List<Vector3>();
     private readonly List<bool> _gizEmbedded = new List<bool>();
     private float _gizVoxelWorld;
@@ -132,9 +131,7 @@ public class ConcealmentMeter : MonoBehaviour
         // else a scaled player is measured at scale² (voxel world positions, broadphase box AND gizmos), which
         // also corrupts EmbeddedPercent. No-op at scale 1; the uniform divide is rotation-independent, which the
         // player's uniform scale guarantees. Mirrors SkinnedColliderBaker's identical fixup.
-        Vector3 ls = targetRenderer.transform.lossyScale;
-        if (ls.x != 1f || ls.y != 1f || ls.z != 1f)
-            RescaleBakedToUnitScale(ls);
+        GeometryUtil.RescaleToUnitScale(_baked, targetRenderer.transform.lossyScale, _vbuf);
 
         _verts = _baked.vertices;
         _tris = _baked.triangles;
@@ -156,7 +153,7 @@ public class ConcealmentMeter : MonoBehaviour
         Matrix4x4 l2w = targetRenderer.transform.localToWorldMatrix;
         // Derive the broadphase box from the ACTUAL transformed geometry, not SkinnedMeshRenderer.bounds
         // (the latter is a root-bone approximation that can be badly offset for a deformed/posed rig).
-        Bounds worldBounds = TransformBounds(l2w, lb);
+        Bounds worldBounds = GeometryUtil.TransformBounds(l2w, lb);
         BuildEnvironmentCandidates(worldBounds);
 
         bool anyEnv = _convex.Count > 0 ||
@@ -213,24 +210,6 @@ public class ConcealmentMeter : MonoBehaviour
         HasResult = true;
     }
 
-    /// <summary>Divides the player's world scale back out of the freshly baked mesh so it is true unit-scale
-    /// local geometry (the space this class raises to world with). Reuses <see cref="_vbuf"/> — no per-eval alloc.</summary>
-    private void RescaleBakedToUnitScale(Vector3 lossyScale)
-    {
-        float ix = lossyScale.x != 0f ? 1f / lossyScale.x : 0f;
-        float iy = lossyScale.y != 0f ? 1f / lossyScale.y : 0f;
-        float iz = lossyScale.z != 0f ? 1f / lossyScale.z : 0f;
-        _baked.GetVertices(_vbuf);
-        for (int i = 0; i < _vbuf.Count; i++)
-        {
-            Vector3 v = _vbuf[i];
-            v.x *= ix; v.y *= iy; v.z *= iz;
-            _vbuf[i] = v;
-        }
-        _baked.SetVertices(_vbuf);
-        _baked.RecalculateBounds();
-    }
-
     /// <summary>
     /// Rasterizes every triangle into the XZ column grid; each column accumulates the Y values
     /// where the surface crosses it (one per triangle whose XZ projection covers the column center).
@@ -389,22 +368,6 @@ public class ConcealmentMeter : MonoBehaviour
         return (hits & 1) == 1;
     }
 
-    /// <summary>World AABB enclosing a local AABB after an affine transform (encapsulates the 8 transformed corners).</summary>
-    private static Bounds TransformBounds(Matrix4x4 m, Bounds local)
-    {
-        Vector3 mn = local.min, mx = local.max;
-        Vector3 c0 = m.MultiplyPoint3x4(mn);
-        Bounds b = new Bounds(c0, Vector3.zero);
-        b.Encapsulate(m.MultiplyPoint3x4(new Vector3(mx.x, mn.y, mn.z)));
-        b.Encapsulate(m.MultiplyPoint3x4(new Vector3(mn.x, mx.y, mn.z)));
-        b.Encapsulate(m.MultiplyPoint3x4(new Vector3(mn.x, mn.y, mx.z)));
-        b.Encapsulate(m.MultiplyPoint3x4(new Vector3(mx.x, mx.y, mn.z)));
-        b.Encapsulate(m.MultiplyPoint3x4(new Vector3(mx.x, mn.y, mx.z)));
-        b.Encapsulate(m.MultiplyPoint3x4(new Vector3(mn.x, mx.y, mx.z)));
-        b.Encapsulate(m.MultiplyPoint3x4(mx));
-        return b;
-    }
-
     private static float AverageScale(Transform t)
     {
         Vector3 s = t.lossyScale;