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/MatchHud.cs

@@ -82,25 +82,19 @@ public class MatchHud : MonoBehaviour
 
     private void EnsureStyles()
     {
-        if (_phaseStyle == null)
+        if (_phaseStyle == null) _phaseStyle = MakeCenteredBoldLabel(22);
+        if (_timeStyle == null) _timeStyle = MakeCenteredBoldLabel(28);
+    }
+
+    private static GUIStyle MakeCenteredBoldLabel(int fontSize)
+    {
+        var style = new GUIStyle(GUI.skin.label)
         {
-            _phaseStyle = new GUIStyle(GUI.skin.label)
-            {
-                alignment = TextAnchor.MiddleCenter,
-                fontSize = 22,
-                fontStyle = FontStyle.Bold,
-            };
-            _phaseStyle.normal.textColor = Color.white;
-        }
-        if (_timeStyle == null)
-        {
-            _timeStyle = new GUIStyle(GUI.skin.label)
-            {
-                alignment = TextAnchor.MiddleCenter,
-                fontSize = 28,
-                fontStyle = FontStyle.Bold,
-            };
-            _timeStyle.normal.textColor = Color.white;
-        }
+            alignment = TextAnchor.MiddleCenter,
+            fontSize = fontSize,
+            fontStyle = FontStyle.Bold,
+        };
+        style.normal.textColor = Color.white;
+        return style;
     }
 }