Toast
The transient receipt for an async action (THEME §12). It wears the primary-button surface — an inverted-ink pill (ink in light, white in dark) — with the label left and a contrast circle on the right. Fixed bottom-center, portaled to <body>. Never an error channel (failures stay inline at their source).
Confirmation
A completed action: the check strokes itself in, then it auto-dismisses (~3s). First used on the billing update-payment save.
Loading
An in-flight action: a spinner instead of the check, and no auto-dismiss (the owner closes it when the work resolves). Used by the multi-role switch.
Undoable
The one action a receipt may carry. It replaces the check, stays up ~7s instead of ~3s, and pauses on hover or focus so the window is reachable. Used where an undo can erase rather than amend — the scheduling approvals, not the person event log.