Add test for invalid unary arcsin operation

Expand test_unary in tests/test_expr.py to assert that calling np.arcsin on the symbolic x raises a TypeError. This adds coverage for invalid unary operations to ensure the code properly reports type errors for unsupported operand types.

Author: Zeroto521

tests/test_expr.py

@@ -260,6 +260,10 @@ def test_unary(model):
     assert cos(1) == np.cos(1)
     assert all(cos([1, 1]) == np.cos([1, 1]))
 
+    # test invalid unary operations
+    with pytest.raises(TypeError):
+        np.arcsin(x)
+
 
 def test_mul():
     m = Model()