This introduces seat_set_raw_focus: a function that manipulates the
focus stack without doing any other behaviour whatsoever. There are a
few places where this is useful, such as where we set focus_inactive
followed by another call to set the real focus again. With this change,
the notify argument to seat_set_focus_warp is also removed as these
cases now use the raw function instead.
A bonus of this is we are no longer emitting window::focus IPC events
when setting focus_inactive, nor are we sending focus/unfocus events to
the surface.
This also fixes the following:
* When running `move workspace to output <name>` and moving the last
workspace from the source output, the workspace::focus IPC event is no
longer emitted for the newly created workspace.
* When splitting the currently focused container, unfocus/focus events
will not be sent to the surface when giving focus_inactive to the newly
created parent, and window::focus events will not be emitted.