Move active tool tracking from TUI message-passing to shared
Arc<RwLock> state. Agent pushes on dispatch, removes on
apply_tool_result. TUI reads during render. Background tasks
show as active until drained at next turn start.
Co-Developed-By: Kent Overstreet <kent.overstreet@linux.dev>
Mechanical rename: src/agent/ -> src/user/, all crate::agent:: ->
crate::user:: references updated. Binary poc-agent renamed to
consciousness with CLI name and user-facing strings updated.
Co-Authored-By: Proof of Concept <poc@bcachefs.org>