feat(dashboard): focus right pane after new-agent bringup completes

The new-agent (`n`) flow's tmux branch was leaving keyboard
focus in the dashboard pane after compose-up + provision
finished and claude landed in the right pane — same situation
as Enter re-attach before its `focus_right_pane` fix. The
operator just spun an agent up; they want to type at it.

Pass `focus_right_pane=True` to `_attach_in_tmux` from the
new-agent flow. `tmux select-pane` runs after the respawn.

claude_bottle/cli/dashboard.py

@@ -1169,9 +1169,12 @@ def _new_agent_flow(
             raise
         if routed:
             bottles[plan.slug] = (cm, bottle, identity)
+            # Move tmux focus to the right pane — the operator
+            # just spun this agent up, they want to type at it.
             return _attach_in_tmux(
                 stdscr, bottle, plan.slug,
                 resume=False, tmux_state=tmux_state,
+                focus_right_pane=True,
             )
 
         # Launch step writes to stderr (image build, network create,