fix: close cipher selection bar when selected items no longer exist

[tmsjngx0]

Fixes #1473.

Problem: After deleting, trashing, archiving or merging all selected items, the selection bar stays open showing "0 selected". The bar's visibility was keyed off the raw selected-id set, while the displayed count was computed from ids filtered against still-existing ciphers — so stale ids kept the bar open.

Fix (3 commits):

• Key the selection bar's empty-check off the filtered list of still-existing ciphers, so the bar closes itself once the selected ciphers are gone (shared createCipherSelectionFlow, affects vault list + duplicates).
• Automatically drop deleted cipher IDs from the selection handle on the duplicates screen.
• Automatically drop selected items from the selection when they are trashed or archived on the vault list.

Tested on desktop: select items → trash/merge all → selection bar now closes instead of lingering with "0 selected".

[github-actions]

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[tmsjngx0]

I have read the CLA Document and I hereby sign the CLA

[tmsjngx0]

recheck