Feature Request: Add loader prop to <GooglePayButton> component

Is your feature request related to a problem? Please describe.
I'm currently integrating the in a React Native app. One common UX expectation is to provide user feedback (like a loading spinner) while the payment flow is initiating or in progress.

Right now, there's no built-in support for a loading indicator or loader prop on the button, which results in either:
The user tapping multiple times
Manual handling outside the component

Describe the solution you'd like
It would be great if the component accepted a loader prop (boolean or custom component), allowing developers to:
Show a spinner or progress indicator on top of the button
Customize the loader style if needed

<GooglePayButton
loading={isProcessing}
loader={}
/>

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.
Wrapping in a parent View and overlaying a loader manually
Additional context
Add any other context or screenshots about the feature request here.

Start by locating the GooglePayButton component and its existing props, then inspect how its press and payment-processing states are handled. Define whether loading and loader are both required, implement the agreed loading behavior, and verify that the button prevents repeated taps while the custom or default indicator is displayed.