feat: desktop Search UI revamp (#7895)

* feat: add ai search entrance

* chore: revamp search recent list

* feat: revamp preview widget

* feat: support click the 'Ask ai button'

* feat: support go to trash when there is no search results

* feat: support AI overview

* fix: typo issue

* fix: empty trash item name

* chore: replace some Dividers to AFDividers

* chore: improve some code logic

* chore: update some icon color

* fix: some UI issue

* chore: adjust some paddings

* fix: align issue for reference sources

* fix: change clear icon's hover effect

* fix: clear search field will not make it unfocus

* chore: make 'Ask AI' button scroll with list

* chore: change the size of search panel

* fix: change mobile search field cancel icon

* feat: support preview panel for recent pages

* fix: some UI issues

* fix: hover to show the reference sources

* fix: some padding issues