Is there any standardized way to keep cashu proofs and overall mints state encrypted on relays?

Imagine if your npub had some ecash balance that seamlessly follows you around any nostr app.

Earn 20k sats on zap.stream, go to shopstr and buy a tshirt, no fiddling around with NWC, secrets, popups or anything. It just works.

Is this already a thing? If not, any reason we can’t?