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/FreeCamController.cs

@@ -57,12 +57,7 @@ public class FreeCamController : MonoBehaviour
 
     CharacterController _controller;
     CinemachineCamera _vcam;
-    float _yaw;     // look target (raw input accumulates here)
-    float _pitch;
-    float _displayYaw;   // smoothed value actually applied to the transform
-    float _displayPitch;
-    float _yawSmoothRef;
-    float _pitchSmoothRef;
+    SmoothedLook _look; // yaw/pitch accumulator + smoothing shared with first person
     Vector3 _moveVelocity;      // smoothed world-space flight velocity
     Vector3 _moveVelocityRef;
     bool _ignoredPlayer;
@@ -110,24 +105,10 @@ public class FreeCamController : MonoBehaviour
     void LookTick()
     {
         Vector2 delta = InputUtil.ReadMouseDelta() * MouseSensitivity.Multiplier;
-        _yaw += delta.x * horizontalSensitivity;
-        float vs = verticalSensitivity * (invertY ? 1f : -1f);
-        _pitch = Mathf.Clamp(_pitch + delta.y * vs, -maxPitch, maxPitch);
-
-        if (lookSmoothTime > 0f)
-        {
-            // SmoothDampAngle is frame-rate-independent and wraps yaw correctly.
-            _displayYaw = Mathf.SmoothDampAngle(_displayYaw, _yaw, ref _yawSmoothRef, lookSmoothTime);
-            _displayPitch = Mathf.SmoothDampAngle(_displayPitch, _pitch, ref _pitchSmoothRef, lookSmoothTime);
-        }
-        else
-        {
-            _displayYaw = _yaw;
-            _displayPitch = _pitch;
-        }
+        _look.Tick(delta, horizontalSensitivity, verticalSensitivity, invertY, maxPitch, lookSmoothTime);
 
         // Rotation is unconstrained by the CharacterController; only position is.
-        transform.rotation = Quaternion.Euler(_displayPitch, _displayYaw, 0f);
+        transform.rotation = _look.Rotation;
     }
 
     void MoveTick()
@@ -153,22 +134,9 @@ public class FreeCamController : MonoBehaviour
         var cam = Camera.main;
         if (!cam) return;
 
-        // CharacterController forbids direct transform writes while enabled, so toggle it for the teleport.
-        bool wasEnabled = _controller.enabled;
-        _controller.enabled = false;
-        transform.SetPositionAndRotation(cam.transform.position, cam.transform.rotation);
-        _controller.enabled = wasEnabled;
+        CharacterTeleport.Move(_controller, transform, cam.transform.position, cam.transform.rotation);
 
-        Vector3 e = transform.rotation.eulerAngles;
-        _yaw = e.y;
-        float p = e.x > 180f ? e.x - 360f : e.x;
-        _pitch = Mathf.Clamp(p, -maxPitch, maxPitch);
-
-        // Snap the smoothed state to the fresh pose so entering freecam never lags/jumps to catch up.
-        _displayYaw = _yaw;
-        _displayPitch = _pitch;
-        _yawSmoothRef = 0f;
-        _pitchSmoothRef = 0f;
+        _look.SyncTo(transform.rotation, maxPitch);
         _moveVelocity = Vector3.zero;
         _moveVelocityRef = Vector3.zero;
     }