Fix focus issues with gpui2 docks (#3606)

* Fixed dock toggling not focusing the terminal element
* Fixed loosing focus on dock close (e.g. cmd-d on the last terminal in
the dock)
* Removed element stateless focus API since it would not work when the
element is not rendered, update all API usages to the stateful one via
`gpui::Subscription`

Release Notes:

- N/A
4684440202Kirill Bulatov committed on 12/12/2023, 3:26:39 PM· committed by GitHubparents97eae4b0140bb8
10 files changedLine totals unavailable