(fix) Library: repair Del hotkey in sidebar, add Clear Queue action to AutoDJ, add hotkeys

[ronso0]

Fixes #13361

1. restore Del hotkey (delete playlist / crate)
2. to not drop the 'clear' function I added a 'Clear Queue' menu action to the AutoDJ root view incl. a confirmatio dialog
3. show Del hotkey in AutoDJ -> Clear and 'Remove crate/playlist' actions

Alternatively, we pick only the fix for 2.5 and the new action goes to 2.6

[ronso0]

ding dong
Is really no one else is bothered by that regression?

We're slowly approaching the 2.5 release so wdyt about this?

Alternatively, we pick only the fix for 2.5 and the new action goes to 2.6

[daschuer]

Oh, just realized that I had a pending minor review comment. Here is it.

[m0dB]

Sorry for not being very responsive, I am travelling. LGTM but not merging as there is a pre-commit issue.

[ronso0]

Thanks.

LGTM but not merging as there is a pre-commit issue.

I guess that was from the tr code suggestions, fixed by merging that commit as fixup.
Ready to roll!