feat: Add "Camera Devices" screen to Example (#1927)

* feat: Add "Camera Devices" screen to Example

* feat: Store device in MMKV

package/example/src/hooks/usePreferredCameraDevice.ts

@@ -0,0 +1,20 @@
+import { useMMKVString } from 'react-native-mmkv'
+import { CameraDevice } from '../../../src/CameraDevice'
+import { useCallback, useMemo } from 'react'
+import { useCameraDevices } from '../../../src/hooks/useCameraDevices'
+
+export function usePreferredCameraDevice(): [CameraDevice | undefined, (device: CameraDevice) => void] {
+  const [preferredDeviceId, setPreferredDeviceId] = useMMKVString('camera.preferredDeviceId')
+
+  const set = useCallback(
+    (device: CameraDevice) => {
+      setPreferredDeviceId(device.id)
+    },
+    [setPreferredDeviceId],
+  )
+
+  const devices = useCameraDevices()
+  const device = useMemo(() => devices.find((d) => d.id === preferredDeviceId), [devices, preferredDeviceId])
+
+  return [device, set]
+}