Disclose the exit tool progressively instead of following every plan-mode
transition. The plan projection records whether a logged plan/mode ever
activated plan mode (stateVersion 4), and the tool's condition admits it
for a step whose selected state is active or once the Session has entered
plan mode. Leaving plan mode now changes only the guidance section, so an
addition-only route no longer drops a declaration from its cached prefix.
A call while plan mode is not committed still fails as unavailable outside
plan mode, and a Session that never entered plan mode does not list the
tool. The Web plan-review fixtures return to master's recording because the
request tool lists no longer change on exit.
Yichen Jiang
752cc5c0c0