Fix action worker watch during paused autoupdate connection

[bastianjoel]

This fixes an issue where the current action worker was displayed as failed after the tab was not in focus for some time.

resolves #6505
Also resolves #6466

[Elblinator]

My requested changes are just redactorial and do not change functional tesing

[bspekker]

The fix doesn't fully work. The import worked once but I maybe have not followed the exact reproduction in that case.
If I focus on a different page while preview is loading, I will get an error message (in the console and on the page).
If I focus on the page while preview is loading, then click on Import and focus on a different page I will also get the error message after checking back ~10 minutes later.

Error in console: "Error: Client has stopped watching worker "participant.import": Process has been assumed to be dead"
Error report: {"id":60,"name":"participant.import","state":"running","created":1788261860,"timestamp":1788262161,"closed":1788262564}