requestWriteContactsPermission
Requests permission to write to contacts (WRITE_CONTACTS).
If permission is already granted, immediately invoke the onGranted callback. Otherwise, launch the PermissionActivity to request permission from the user.
Note: Ensure to add the following permission in the app's manifest file:
Parameters
onGranted
Callback invoked if permission is granted.
onDenied
Callback invoked if permission is denied.