Rationale: Sticky containers are always assigned to the visible
workspace.
The basic idea here is to check the destination's output (move.c:190).
But if the command was `move container to workspace x` then a workspace
might have been created for it. We could destroy the workspace in this
case, but that results in unnecessary IPC events.
To avoid this, the logic for `move container to workspace x` has been
adjusted. It now delays creating the workspace until the end, and uses
`workspace_get_initial_output` to determine and check the output before
creating it.
Introduces a command to manually set urgency, as well as rendering of
urgent views, sending the IPC event, removing urgency after focused for
one second, and matching urgent views via criteria.
When you spawn a process with the exec command, sway now notes the
workspace you had focused and the pid of the child process, then assigns
that workspace to the child when its window appears.
Some of this is carried over from sway 0.15, but with some major
refactoring and centralization of state.