doc: validity public property

Author: pozil

README.md

@@ -269,6 +269,7 @@ Sometimes, you may want to pass extra data from the lookup component to Apex. To
 | `required`            | `Boolean`                                                                                     | Whether the lookup is a required field. Note: Property can be set with `<c-lookup required>`.                                                                                                                                                                                                                                                                                                                                                                                       | `false`         |
 | `scrollAfterNItems`   | `Number`                                                                                      | A null or integer value used to force overflow scroll on the result listbox after N number of items.<br/>Valid values are `null`, `5`, `7`, or `10`.<br/>Use `null` to disable overflow scrolling.                                                                                                                                                                                                                                                                                  | `null`          |
 | `selection`           | `[LookupSearchResult]` OR `LookupSearchResult`                                                | Lookup initial selection if any. Array for multi-entry lookup or an Object for single entry lookup.                                                                                                                                                                                                                                                                                                                                                                                 | `[]`            |
+| `validity`            | `Boolean`                                                                                     | Read-only property that reports whether there are errors or not (see `errors`).                                                                                                                                                                                                                                                                                                                                                                                                     | `false`         |
 | `variant`             | `String`                                                                                      | Changes the appearance of the lookup. Accepted variants:<br/>`label-stacked` - places the label above the lookup.<br/>`label-hidden` - hides the label but make it available to assistive technology.<br/>`label-inline` - aligns horizontally the label and lookup.                                                                                                                                                                                                                | `label-stacked` |
 
 ### Functions