* feat(dashboard): add session:progress board tile rendering the live progress card
Advertise the core-owned widget kind via hello controlUiWidgetKinds at operator.read.
Render it inline without an iframe from the session-progress-cards store.
Pin it with dashboard tool widget_put using pluginKind session:progress and optional props.sessionKey.
Follow up the progress-card unification from #125125.
* fix(dashboard): surface session progress load failures
Record protected progress-card read failures in the shared per-session store.
Render an actionable board-tile error with retry instead of indefinite loading.
Cover the rejected-read and successful-retry flow at the widget boundary.
* fix(dashboard): honor progress tile access and activity
Avoid progress-card reads while a retained board is inactive.
Distinguish sharing denial from transient load failures and show the correct remedy.
Qualify cross-session pinning docs and cover activation plus denial behavior.
Peter Steinberger
b228c83bfc