Show which timescale is default for auto-update filters

### Issue Details

There is no hint as to what the timescale for "Default" is when auto-updating filters.


### Proposed solution

I propose that default be placed next to the timescale that is default for less confusion.


### Alternative solution

_No response_

Start by locating the auto-updating filters UI shown in the issue screenshots and identify where the available timescales and “Default” label are rendered. Confirm which timescale is currently default, then make the default indicator visible next to it and verify the wording and layout in the affected browser-extension UI.

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