Body step 2.1: climbing, mantling, crawling, legs, playground, 144 Hz

- Step rule + lower-body collider: no walking onto tables, steps <= 0.35 m
- Structural hand strength: two-hand mantle/pull-up works, one hand can't
- Arms aim from the physical shoulder horizontally, keep True Body pose vertically
- Crawl pose, crawl carry, 35 deg slope limit, ground feed-forward ignores
  play-space corrections (fixes a runaway feedback loop)
- Grab static world (climbing), procedural visual legs
- Playground sandbox; menu strength slider, spectator (old drag) and turn toggles
- Physics 144 Hz with interpolation; legacy chase-body spikes pin 90 Hz
- RagdollSpike: 27 phases incl. mantle, pull-up, crawl, ledge drop, ramps

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

scripts/WorldPanel.cs

@@ -61,6 +61,7 @@ public partial class WorldPanel : Node3D
         _menu.ResetPropsRequested += () =>
         {
             _propShop.Respawn();
+            GetNodeOrNull<Playground>("../../Playground")?.Reset();
             _menu.Log("Props reset");
         };
         _menu.PingRequested += () =>
@@ -75,6 +76,9 @@ public partial class WorldPanel : Node3D
         _click = MakeTone(900f, 25, 0.35f, 1f);
         _ping = MakeTone(1320f, 4, 0.3f, 3f);
         _menu.ClickVolumeSlider.ValueChanged += v => _click.VolumeDb = Mathf.LinearToDb((float)v / 70f);
+        _menu.StrengthChanged += v => PlayerRagdoll.Strength = v;
+        _menu.SmoothTurnToggled += on => PlayerRig.SmoothTurn = on;
+        _menu.SpectatorToggled += PlayerRig.SetSpectator;
 
         SetPanelActive(false);
     }