feat: adds metadata property details for web elements (#47)

docs/sdks/web/javascript/methods.mdx

@@ -2,7 +2,7 @@
 sidebar_label: Methods & Events
 ---
 
-import { Alert, Alerts } from "@site/src/components/shared/Alert";
+import {Alert, Alerts} from "@site/src/components/shared/Alert";
 
 # Elements Method & Events
 
@@ -106,6 +106,17 @@ cardElement.on("change", (changeEvent) => {
   <a href="mailto:info@basistheory.com">info@basistheory.com.</a>
 </Alert>
 
+#### Metadata
+
+Instead of subscribing to events, the same properties can be accessed at any time from the `metadata` property on all elements.
+
+Additionally, the card related event [change events](#changeevent) can be accessed from the `cardMetadata` property only on [Card](/docs/sdks/web/javascript/types#card-element) and [CardNumber](/docs/sdks/web/javascript/types#card-number-element) elements.
+
+| Attribute      | Eligible Elements                                                                                                          | Attributes                                    |
+|----------------|----------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------|
+| `metadata`     | All                                                                                                                        | `complete`, `valid`, `maskSatisfied`, `empty` |
+| `cardMetadata` | [card](/docs/sdks/web/javascript/types#card-element)<br/>[cardNumber](/docs/sdks/web/javascript/types#card-number-element) | `cardLast4`, `cardBin`, `cardBrand`           |
+
 #### FieldError
 
 ```json showLineNumbers