PlaytoliaNotifications

On Windows, these methods do nothing.

Method	Parameters	Returns	Notes
`GetState()`	(none)	`PushState`	Returns the current notification state.
`Refresh()`	(none)	`void`	Reads the permission state again.
`RegisterPushToken(token)`	`string`	`void`	Sends the FCM token to the backend.
`RequestPushPermission()`	(none)	`void`	Shows the permission dialog of the operating system.
`OpenNotificationSettings()`	(none)	`void`	Opens the notification settings of the operating system.
`GetPermission()`	(none)	`string`	Returns `"Granted"`, `"DeniedAlways"`, or `"NotGranted"`.
`SendTestPush(title, body, data)`	`string`, `string`, `string` (optional)	`void`	Asks the backend to send a push to the signed-in player, to check delivery.
`AddListener(listener)`	`Action`	`void`	Calls the listener on each change of the state.
`RemoveListener(listener)`	`Action`	`void`	Deletes the listener.

Field	Type	Notes
`Preferences`	`Dictionary<string, bool>`	Player preferences for each notification category
`Permission`	`string`	`"Granted"`, `"DeniedAlways"`, or `"NotGranted"`