Line3: Fix closest point in `distanceSqToLine3()`. (#32878)

src/math/Line3.js

@@ -284,12 +284,10 @@ class Line3 {
 
 		}
 
-		c1.copy( p1 ).add( _d1.multiplyScalar( s ) );
-		c2.copy( p2 ).add( _d2.multiplyScalar( t ) );
+		c1.copy( p1 ).addScaledVector( _d1, s );
+		c2.copy( p2 ).addScaledVector( _d2, t );
 
-		c1.sub( c2 );
-
-		return c1.dot( c1 );
+		return c1.distanceToSquared( c2 );
 
 	}