implement remaining functions in mlx.numpy.py (#20816)

* mlx.numpy.py implementation

* formatting

Author: acsweet

keras/src/backend/mlx/linalg.py

@@ -7,7 +7,10 @@
 
 
 def det(a):
-    raise NotImplementedError("det not yet implemented in mlx.")
+    # TODO: Swap to mlx.linalg.det when supported
+    a = jnp.array(a)
+    output = jnp.linalg.det(a)
+    return mx.array(output)
 
 
 def eig(a):