Add close_session helpers and CLI to append vault session logs, engagement-
scoped metrics, duty Kai charges, and client reports. Rejects sensitive
summaries. Pilot smoke-closed once; prepare points operators at close-session.
Add kaizen-agentic engagement subcommands (list, show, validate, checklist,
phase, prepare, staff, quote, scrub, export-handoff) backed by engagement.py
for file-based pilot lifecycle. Tests cover staff/validate/phase/prepare and
the railiance01 pilot smoke path.
