Daemon failures need to be more noisy

# Summary

When a workflow contains a daemon task that stops (error/wrong command), Argo no longer interpolates template variables `{{steps.my-task.ip}}`. While this makes logical sense to not supply an IP Address that does not exist, it does not bubble up the root cause that the daemon is not running.

I would propose instead of not interpolating the variable, argo instead interpolates with the string ``

# Use Cases

When would you use this?

Debugging issues with daemon tasks/steps

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**Message from the maintainers**:

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Start by tracing daemon-task failure handling and interpolation of {{steps.my-task.ip}}. Check how an error or wrong command is represented when the daemon stops, then add coverage showing the variable becomes and that the root cause is visible to the workflow user.

Written by the indexing model from the issue text.