FR: Pay or subscribe via android, iOS in-app payments

### What are you trying to do?

I would like to consider subscribing to Tailscale in the future, but I have no intention of getting a credit card.

### How should we solve this?

It will be a convenient way to subscribe to the service via Android because I can connect it to my e-wallet.

### What is the impact of not solving this?

Less convenient for someone who doesn't have a credit card.

### Anything else?

_No response_