**Semantic Clarification**: Controls *where the widget's data comes from* — its own search vs. the embedding layout's.

**Valid Values**:
- `false` (self-contained, the common default): the widget uses the `search` baked into its own definition. Best for landing pages and dashboards that always show the same scope.
- `true` (embedding override): the embedding layout's data source supplies the widget's `pages`, so the same widget renders data scoped to the host record. Best for detail widgets (e.g. KPI tiles on a record page).

**Note**: When `false`, a `VALID_INCOMPLETE` warning about the `selection` attribute is expected and harmless. When `true`, configure the layout's data source (`search` / `tableWidgetId` / `selection`) accordingly.