Remove RoomDirectorySearch feature flag — always enable the feature (#6736)

* Remove RoomDirectorySearch feature flag, always enable the feature

Co-authored-by: stefanceriu <637564+stefanceriu@users.noreply.github.com>

* Apply ktlint formatting

Co-authored-by: jmartinesp <480955+jmartinesp@users.noreply.github.com>

* Update screenshots

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: stefanceriu <637564+stefanceriu@users.noreply.github.com>
Co-authored-by: jmartinesp <480955+jmartinesp@users.noreply.github.com>
Co-authored-by: ElementBot <android@element.io>

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