Include rotation in movement detection for foot blend

When turning on the spot, hips translate very little but rotate
significantly. The speed calculation only used horizontal translation,
so rotation kept blendWeight at 1.0 and feet stayed planted at their
old positions instead of following the turn animation.

Now angular velocity of the hips is converted to equivalent linear speed
at foot level (angularSpeed * legLength) and added to the total speed.
Rotation triggers the animation blend just like walking does, so feet
follow the turning animation and re-plant at correct positions when
the turn completes.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: dooly123

Basis/Packages/com.basis.framework/IK/FootPlacement/BasisLocalFootDriver.cs

@@ -79,6 +79,7 @@ public class BasisLocalFootDriver
     // Blend weight: 0 = full animation, 1 = full ground placement
     float blendWeight = 1f;
     Vector3 lastHipsWorldPos;
+    Quaternion lastHipsWorldRot;
 
     // ===================== Public Results =====================
 
@@ -210,6 +211,7 @@ public void Initialize()
         InitFootPose(rightState);
 
         lastHipsWorldPos = hipsTransform.position;
+        lastHipsWorldRot = hipsTransform.rotation;
         blendWeight = 1f;
 
         initialized = true;
@@ -266,13 +268,26 @@ public void Update(
         if (!initialized || avatarTransform == null || hipsTransform == null) return;
         if (deltaTime <= 0f) return;
 
-        // --- Compute player speed from hips movement (horizontal only) ---
+        // --- Compute player speed from hips movement + rotation ---
         Vector3 currentHipsPos = hipsTransform.position;
+        Quaternion currentHipsRot = hipsTransform.rotation;
+
         Vector3 hipsDelta = currentHipsPos - lastHipsWorldPos;
+        float angleDelta = Quaternion.Angle(lastHipsWorldRot, currentHipsRot);
+
         lastHipsWorldPos = currentHipsPos;
+        lastHipsWorldRot = currentHipsRot;
+
+        // Horizontal translation speed
+        float linearSpeed = new Vector2(hipsDelta.x, hipsDelta.z).magnitude / deltaTime;
+
+        // Angular speed converted to equivalent foot-level linear speed:
+        // how fast the feet move in a circle when the body rotates in place
+        float avgLegLen = (leftState.totalLegLen + rightState.totalLegLen) * 0.5f;
+        float rotationalSpeed = (angleDelta * Mathf.Deg2Rad * avgLegLen) / deltaTime;
 
-        // Horizontal speed only (ignore vertical movement from crouching/jumping)
-        float playerSpeed = new Vector2(hipsDelta.x, hipsDelta.z).magnitude / deltaTime;
+        // Combined speed: either translation or rotation triggers animation blend
+        float playerSpeed = linearSpeed + rotationalSpeed;
 
         // --- Compute blend weight: 0 = full animation, 1 = full ground placement ---
         float targetWeight = 1f - Mathf.InverseLerp(idleSpeedThreshold, walkSpeedThreshold, playerSpeed);