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/PlayerCharacterController.cs

@@ -486,17 +486,12 @@ public class PlayerCharacterController : MonoBehaviour
     }
 
     /// <summary>
-    /// Kill-plane rescue: snap the avatar back to its captured spawn point and clear all momentum. The
-    /// CharacterController overrides direct transform writes, so it is toggled around the move (same
-    /// pattern as <see cref="NetworkPlayerSetup.PlaceOnSpawnRing"/>). Owner-only; the authoritative
-    /// NetworkTransform replicates the new position to remotes.
+    /// Kill-plane rescue: snap the avatar back to its captured spawn point and clear all momentum.
+    /// Owner-only; the authoritative NetworkTransform replicates the new position to remotes.
     /// </summary>
     private void RescueToSpawn()
     {
-        bool reenable = _controller && _controller.enabled;
-        if (_controller) _controller.enabled = false;
-        transform.position = _spawnPosition;
-        if (_controller) _controller.enabled = reenable;
+        CharacterTeleport.Move(_controller, transform, _spawnPosition);
 
         _verticalVelocity = 0f;
         _horizontalVelocity = Vector3.zero;
@@ -800,12 +795,12 @@ public class PlayerCharacterController : MonoBehaviour
         }
         else if (_climbLeftGround && vEff > 0f)
         {
-            TopOutDetach(); // topped out upward onto walkable ground: hop over the lip (holding the up key carries on)
+            TopOutDetach();
             return;
         }
         else if (_climbLeftGround || vEff < 0f)
         {
-            ExitWallClimb(); // descended to the floor, or pulling down/away at the base: let go, no hop
+            ExitWallClimb();
             return;
         }
 
@@ -989,34 +984,16 @@ public class PlayerCharacterController : MonoBehaviour
     /// </summary>
     private bool ProbeWall(out Vector3 normal, out float gap)
     {
-        normal = _wallNormal;
-        gap = 0f;
-
         Vector3 origin = WorldCapsuleCenter;
         Vector3 dir = -_wallNormal;
         float extent = CapsuleExtent(dir);
         float maxDist = extent + wallMaxOffset + ProbeReachSlack * CapsuleScale;
 
-        int count = Physics.RaycastNonAlloc(
-            origin, dir, _wallProbe, maxDist, ~0, QueryTriggerInteraction.Ignore);
+        if (NearestClimbHit(origin, dir, maxDist, extent, ceilingOnly: false, out normal, out gap))
+            return true;
 
-        float best = float.MaxValue;
-        bool found = false;
-        for (int i = 0; i < count; i++)
-        {
-            if (IsPlayerCollider(_wallProbe[i].collider) || IsNoClimb(_wallProbe[i].collider)) // skip self, other player avatars, and no-climb surfaces
-                continue;
-            if (_wallProbe[i].distance < best)
-            {
-                best = _wallProbe[i].distance;
-                normal = _wallProbe[i].normal;
-                found = true;
-            }
-        }
-
-        if (found)
-            gap = Mathf.Max(0f, best - extent);
-        return found;
+        normal = _wallNormal;
+        return false;
     }
 
     /// <summary>
@@ -1035,15 +1012,32 @@ public class PlayerCharacterController : MonoBehaviour
     /// </summary>
     private bool ProbeCeiling(out Vector3 normal, out float gap)
     {
-        normal = Vector3.down;
-        gap = 0f;
-
         Vector3 origin = WorldCapsuleCenter;
         float half = WorldHalfHeight;
         float maxDist = half + wallMaxOffset + ProbeReachSlack * CapsuleScale;
 
+        if (NearestClimbHit(origin, Vector3.up, maxDist, half, ceilingOnly: true, out normal, out gap))
+            return true;
+
+        normal = Vector3.down;
+        return false;
+    }
+
+    /// <summary>
+    /// Raycasts along <paramref name="dir"/> and returns the nearest hit that a climb probe accepts
+    /// (player avatars and no-climb surfaces never count; <paramref name="ceilingOnly"/> additionally
+    /// rejects non-ceiling normals). <paramref name="gap"/> is the clearance beyond the capsule's
+    /// support <paramref name="extent"/> along the probe direction. False = no valid hit
+    /// (<paramref name="normal"/>/<paramref name="gap"/> are then zero; callers supply their fallback).
+    /// </summary>
+    private bool NearestClimbHit(Vector3 origin, Vector3 dir, float maxDist, float extent,
+        bool ceilingOnly, out Vector3 normal, out float gap)
+    {
+        normal = Vector3.zero;
+        gap = 0f;
+
         int count = Physics.RaycastNonAlloc(
-            origin, Vector3.up, _wallProbe, maxDist, ~0, QueryTriggerInteraction.Ignore);
+            origin, dir, _wallProbe, maxDist, ~0, QueryTriggerInteraction.Ignore);
 
         float best = float.MaxValue;
         bool found = false;
@@ -1051,7 +1045,7 @@ public class PlayerCharacterController : MonoBehaviour
         {
             if (IsPlayerCollider(_wallProbe[i].collider) || IsNoClimb(_wallProbe[i].collider))
                 continue;
-            if (_wallProbe[i].normal.y >= CeilingNormalThreshold) // not a ceiling
+            if (ceilingOnly && _wallProbe[i].normal.y >= CeilingNormalThreshold) // not a ceiling
                 continue;
             if (_wallProbe[i].distance < best)
             {
@@ -1062,7 +1056,7 @@ public class PlayerCharacterController : MonoBehaviour
         }
 
         if (found)
-            gap = Mathf.Max(0f, best - half);
+            gap = Mathf.Max(0f, best - extent);
         return found;
     }