Users can publish payment addresses for other cryptocurrencies and
payment apps (payto tags per draft NIP-A3) and pay other users
through them.
- NipA3.kt: parse/build payto tags, type validation, payto:// and
native wallet URIs, recognized-type stylization
- PaymentTargetRepository: LRU + SharedPrefs cache per pubkey;
stores empty lists so cleared targets propagate
- ZapDialog: "Other ways to pay" chip section; targets-only dialog
when lightning zapping isn't possible but targets exist
- PaymentTargetSheet: QR, copy, open-in-wallet bottom sheet
- Wallet settings: manage and publish own targets with network
read-back before editing to avoid clobbering the replaceable event
- Profile screen: targets shown under the lightning address
- On-demand fetch only (zap dialog / profile open), ingested via
EventRouter with created_at freshness guard