Why: after login the store's identity epoch and the capability probe each
settle once more; the app closes open workspaces on identity change, so
clicking the sidebar entry too early raced the overlay close (intermittent
加载中 hang, caught across I4 e2e runs).
Evidence: instrumented probe (rows=2 parsed then overlay closed on identity
bump); settled-login rerun follows on the Dev I4 card.
Impact: spec stability only.
Refs: rollout I4