Refactor scripts: dedup remainder, remove dead code, perf hardening

Iteration 4 over Assets/Scripts (no component/file splits, no Unity assets touched):

Dedup:
- Route inline cursor-release, material guards, Ctrl-held and undo/redo
  input through existing InputUtil / SetMatFloat helpers
- Add ungated InputUtil.KeyPressedThisFrame; GameplayKeyPressed builds on it
- Unify FindDeep/FindDeepChild into GeometryUtil.FindDeep

Dead code / stale docs:
- Remove unused code-gen bake path (HsvColorPicker.Build, PaintHud factory)
- Drop unreferenced symbols (SubPhaseChanged event, LocalPhaseDuration,
  IsLocalSceneMain, MouseSensitivity.Changed, IsPaused, InSession,
  NetworkControlled, PreviousPose, JointCount, voxel-count accessors)
- Fix incorrect PlayerRole / PaintHud / Pick / PlayerPose docs

Perf / robustness (behaviour-neutral):
- ConcealmentMeter.Evaluate: reuse vertex/topology buffers, two-pointer
  crossing count
- BuildMeshCaches: alloc-free vertex copy, cached topology/UVs
- Guard all PlayerPaintSync LogSync sites behind logSync
- Cache LocalViewerIsHunter / controller / CanShoot / TypingGuard lookups;
  dedup LocalIsHunter with MatchHud
- Change-guard RefreshEmissionColor and HeroCutout.Disarm
- Cache scene/countdown string comparisons per frame
- Grow NonAlloc buffers and log-once on saturation

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Assets/Scripts/PlayerPoseController.cs

@@ -121,9 +121,6 @@ public class PlayerPoseController : MonoBehaviour
     /// <summary>Locomotion category resolved this frame (which clip the active pose is playing). The owner publishes it for network sync.</summary>
     public Locomotion CurrentLocomotion => _currentLocomotion;
 
-    /// <summary>True once this avatar is driven by replicated network state instead of local input/physics.</summary>
-    public bool NetworkControlled => _networkControlled;
-
     /// <summary>
     /// Switches this avatar to network-driven animation: local input, the sprint-reset, the per-pose
     /// collision capsule and camera framing are all skipped; pose index and locomotion are supplied by
@@ -248,9 +245,6 @@ public class PlayerPoseController : MonoBehaviour
     /// <summary>Advances to the next pose, wrapping at the end of the list.</summary>
     public void NextPose() => SetPoseIndex(_currentIndex + 1);
 
-    /// <summary>Steps back to the previous pose, wrapping at the start of the list.</summary>
-    public void PreviousPose() => SetPoseIndex(_currentIndex - 1);
-
     /// <summary>Selects a pose by index, wrapping into range so cycling never goes out of bounds.</summary>
     public void SetPoseIndex(int index) => _currentIndex = WrapIndex(index);