Log tail + forwarding

### Expected Behavior

When forwarding logs to Splunk, aio rt logs command does not works and sends this message:
> Namespace is configured with custom log forwarding destination: 'splunk_hec'. Please use corresponding logging platform to view logs.

### Actual Behavior

If you run `aio rt logs --tail` in 1 tab and configure Splunk forwarding in a different tab, then you will continue to see logs both in Splunk and terminal until you decide to close your terminal.

Reproduce `aio rt logs --tail` while configuring Splunk forwarding in a separate terminal, then trace the CLI paths handling log tailing and forwarding. Clarify the intended terminal behavior first; done means the command consistently follows that behavior without the reported conflicting output.

Written by the indexing model from the issue text.