Two additional fixes to prevent agents from writing .cw/output/ in the
wrong location:
1. Always create .cw/output/ at the agent workdir root during spawn,
even when no inputContext is provided. This gives the agent a visible
anchor directory so it doesn't create one inside a project subdir.
2. Add absolute output path instruction to the workspace layout prompt
for multi-project agents, explicitly telling them to write .cw/output/
relative to the workdir root, not their current cd location.
17f92040c7