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/PlayerPaintSync.cs

@@ -233,20 +233,14 @@ public class PlayerPaintSync : NetworkBehaviour
         // its own material via HUD + persistence).
         if (!IsOwner && _camoApplyPending && _painter && _painter.IsReady)
         {
-            Vector3 c = _camo.Value;
-            _painter.CamoHalfLambert = c.x;
-            _painter.CamoHalfLambertBrightness = c.y;
-            _painter.CamoSpecularDampen = c.z;
+            _painter.CamoKnobs = _camo.Value;
             _camoApplyPending = false;
         }
 
         // Remote replica: apply the owner's painted-height knobs once the material exists / on change.
         if (!IsOwner && _heightApplyPending && _painter && _painter.IsReady)
         {
-            Vector3 h = _height.Value;
-            _painter.OcclusionThreshold = h.x;
-            _painter.HeightNormalIntensity = h.y;
-            _painter.ParallaxIntensity = h.z;
+            _painter.HeightKnobs = _height.Value;
             _heightApplyPending = false;
         }
 
@@ -274,11 +268,11 @@ public class PlayerPaintSync : NetworkBehaviour
         // published (it would briefly flatten remotes' lighting until the real value lands).
         if (_painter && _painter.IsReady)
         {
-            var camo = new Vector3(_painter.CamoHalfLambert, _painter.CamoHalfLambertBrightness, _painter.CamoSpecularDampen);
+            Vector3 camo = _painter.CamoKnobs;
             if (_camo.Value != camo)
                 _camo.Value = camo;
 
-            var height = new Vector3(_painter.OcclusionThreshold, _painter.HeightNormalIntensity, _painter.ParallaxIntensity);
+            Vector3 height = _painter.HeightKnobs;
             if (_height.Value != height)
                 _height.Value = height;
         }
@@ -365,20 +359,31 @@ public class PlayerPaintSync : NetworkBehaviour
     [ServerRpc]
     private void SubmitRestoreServerRpc(int seq, int id) => ApplyRestoreClientRpc(seq, id);
 
-    [ClientRpc]
-    private void ApplyStampsClientRpc(int seq, PaintStampNet[] stamps)
+    /// <summary>
+    /// Common gate for the replicated commands: the owner already applied them locally, so only remotes
+    /// (incl. the host's replica) proceed; during a snapshot transfer the event is buffered instead.
+    /// Returns true when the caller should apply the event live.
+    /// </summary>
+    private bool GateRemoteEvent(NetEvent ev)
     {
-        // The owner already painted these locally; only remotes (incl. the host's replica) replay them.
         if (IsOwner || !_painter)
-            return;
+            return false;
 
-        _seqHorizon = seq; // server replica tracks this as the snapshot cutoff source
+        _seqHorizon = ev.seq; // server replica tracks this as the snapshot cutoff source
 
         if (_awaitingSnapshot)
         {
-            _buffered.Add(new NetEvent { seq = seq, kind = NetKind.Stamps, stamps = stamps });
-            return;
+            _buffered.Add(ev);
+            return false;
         }
+        return true;
+    }
+
+    [ClientRpc]
+    private void ApplyStampsClientRpc(int seq, PaintStampNet[] stamps)
+    {
+        if (!GateRemoteEvent(new NetEvent { seq = seq, kind = NetKind.Stamps, stamps = stamps }))
+            return;
 
         for (int i = 0; i < stamps.Length; i++)
             _painter.ApplyNetworkStamp(stamps[i]);
@@ -387,17 +392,9 @@ public class PlayerPaintSync : NetworkBehaviour
     [ClientRpc]
     private void ApplyCheckpointClientRpc(int seq, int id)
     {
-        if (IsOwner || !_painter)
+        if (!GateRemoteEvent(new NetEvent { seq = seq, kind = NetKind.Checkpoint, id = id }))
             return;
 
-        _seqHorizon = seq;
-
-        if (_awaitingSnapshot)
-        {
-            _buffered.Add(new NetEvent { seq = seq, kind = NetKind.Checkpoint, id = id });
-            return;
-        }
-
         _painter.RemoteCommitCheckpoint(id);
         LogSync($"committed checkpoint {id} (seq {seq})");
     }
@@ -405,17 +402,9 @@ public class PlayerPaintSync : NetworkBehaviour
     [ClientRpc]
     private void ApplyRestoreClientRpc(int seq, int id)
     {
-        if (IsOwner || !_painter)
+        if (!GateRemoteEvent(new NetEvent { seq = seq, kind = NetKind.Restore, id = id }))
             return;
 
-        _seqHorizon = seq;
-
-        if (_awaitingSnapshot)
-        {
-            _buffered.Add(new NetEvent { seq = seq, kind = NetKind.Restore, id = id });
-            return;
-        }
-
         // Reproduce the undo/redo from this peer's own history; if it doesn't hold that checkpoint (an
         // undo past this peer's join point), fetch a fresh snapshot of the resulting state instead.
         if (_painter.RemoteRestoreTo(id))
@@ -520,14 +509,20 @@ public class PlayerPaintSync : NetworkBehaviour
         int xferId = ++_xferOut;
 
         BeginSnapshotClientRpc(xferId, data.Length, capturedSeq, baselineId, send);
+        yield return SendChunked(data, (off, chunk) => SnapshotChunkClientRpc(xferId, off, chunk, send));
+        EndSnapshotClientRpc(xferId, send);
+    }
 
+    /// <summary>Feeds a blob chunk-wise into sendChunk(offset, chunk), throttled to snapshotChunksPerFrame.</summary>
+    private IEnumerator SendChunked(byte[] data, System.Action<int, byte[]> sendChunk)
+    {
         int sentThisFrame = 0;
         for (int off = 0; off < data.Length; off += snapshotChunkBytes)
         {
             int len = Mathf.Min(snapshotChunkBytes, data.Length - off);
             var chunk = new byte[len];
             System.Array.Copy(data, off, chunk, 0, len);
-            SnapshotChunkClientRpc(xferId, off, chunk, send);
+            sendChunk(off, chunk);
 
             if (++sentThisFrame >= snapshotChunksPerFrame)
             {
@@ -535,8 +530,6 @@ public class PlayerPaintSync : NetworkBehaviour
                 yield return null; // spread the burst so the reliable window does not overflow
             }
         }
-
-        EndSnapshotClientRpc(xferId, send);
     }
 
     [ClientRpc]
@@ -564,8 +557,14 @@ public class PlayerPaintSync : NetworkBehaviour
     private void SnapshotChunkClientRpc(int xferId, int offset, byte[] chunk, ClientRpcParams p = default)
     {
         if (xferId != _activeXferId || _snapBuffer == null) return; // stale chunk from a superseded transfer
-        if (offset >= 0 && offset + chunk.Length <= _snapBuffer.Length)
-            System.Array.Copy(chunk, 0, _snapBuffer, offset, chunk.Length);
+        CopyChunkInto(_snapBuffer, offset, chunk);
+    }
+
+    /// <summary>Copies a received chunk into the reassembly buffer, ignoring out-of-bounds offsets.</summary>
+    private static void CopyChunkInto(byte[] buffer, int offset, byte[] chunk)
+    {
+        if (offset >= 0 && offset + chunk.Length <= buffer.Length)
+            System.Array.Copy(chunk, 0, buffer, offset, chunk.Length);
     }
 
     [ClientRpc]
@@ -611,22 +610,7 @@ public class PlayerPaintSync : NetworkBehaviour
     private IEnumerator UploadSnapshot(byte[] data, int cutoff, int baselineId, bool broadcast, ulong target)
     {
         BeginUploadServerRpc(data.Length, cutoff, baselineId, broadcast, target);
-
-        int sentThisFrame = 0;
-        for (int off = 0; off < data.Length; off += snapshotChunkBytes)
-        {
-            int len = Mathf.Min(snapshotChunkBytes, data.Length - off);
-            var chunk = new byte[len];
-            System.Array.Copy(data, off, chunk, 0, len);
-            UploadChunkServerRpc(off, chunk);
-
-            if (++sentThisFrame >= snapshotChunksPerFrame)
-            {
-                sentThisFrame = 0;
-                yield return null; // spread the burst so the reliable window does not overflow
-            }
-        }
-
+        yield return SendChunked(data, (off, chunk) => UploadChunkServerRpc(off, chunk));
         EndUploadServerRpc();
     }
 
@@ -644,8 +628,7 @@ public class PlayerPaintSync : NetworkBehaviour
     private void UploadChunkServerRpc(int offset, byte[] chunk)
     {
         if (_uploadBuffer == null) return;
-        if (offset >= 0 && offset + chunk.Length <= _uploadBuffer.Length)
-            System.Array.Copy(chunk, 0, _uploadBuffer, offset, chunk.Length);
+        CopyChunkInto(_uploadBuffer, offset, chunk);
     }
 
     [ServerRpc]