- Update `AcpThreadView.insert_selections` to take into account whether
the user is currently editing an existing message and, if it is, insert
the selection into that message instead of the thread's message editor
- Update Window's default keymap to use the `agent::QuoteSelection`
action instead of the deprecated `assistant::QuoteSelection` action
- Introduce `AcpThreadView.active_editor` to allow callers to retrieve
either the thread view's message editor or the editor for the message
being edited, in case `AcpThreadView.editing_message` is not `None`
- Improve `AcpThreadView.focus_handle` to focus on the message being
currently edited in case the user navigates back to the editor and then
to the thread view again, all while editing a message
- Add tests for `AcpThreadView.insert_selections`, ensuring that the
selection is inserted in the message being currently edited, if a
message is being edited, or the thread view's message editor if no
message is being edited
Closes#39693
Release Notes:
- Improved `agent: quote selection` to also work for a message that was
already sent but is being edited
---------
Co-authored-by: Ben Brandt <benjamin.j.brandt@gmail.com>
