docs(QrcodeCapture): add capture attribute

docs/api/QrcodeCapture.md

@@ -73,6 +73,20 @@ You can even remove or replace already defined attributes:
 />
 ```
 
+### `capture`
+
+- **Payload Type:** `'' | null | 'user' | 'environment'`
+- **Default:** `""`
+
+The capture attribute specifies that, optionally, a new file should be captured, and which device should be used to capture that new media of a type defined by the accept attribute.
+[html docs](https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/capture)
+
+By default this is set to `''` to open the camera, when available. You can also provide a `null` value to disable this preset.
+
+```html
+<qrcode-capture :capture="null" />
+```
+
 ## Slots
 
 > no slots