fixed guidance only pulling things towards the middle and added CA QP CBF code

geometries/@spherical/random.m

@@ -0,0 +1,15 @@
+function r = random(obj)
+    arguments (Input)
+        obj (1, 1) {mustBeA(obj, 'spherical')};
+    end
+    arguments (Output)
+        r (1, 3) double
+    end
+    y = (rand - 0.5) * 2; % uniform draw on [-1, 1]
+    R = sqrt(1 - y^2);
+    lon = (rand - 0.5) * 2 * pi; % uniform draw on [-pi, pi]
+    s = [R * sin(lon), y, R * cos(lon)]; % random point on surface
+    r = s * rand^(1/3); % scaled to random normalized radius [0, 1]
+
+    r = obj.center + obj.radius * r;
+end