bug: errors when visualizing streams terminating with an error

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Describe the bug
When visualizing a stream that terminates in an error:

• The output termination node is not an error
• An error message is spammed to the snack bar and console

To Reproduce
Steps to reproduce the behavior:

1. Visualize a stream then terminates with an error
2. See the attached gif

Expected behavior

• The output termination node should be an error (i.e. error symbol)

Screenshots

Desktop (please complete the following information):

• Browser: Brave