feat: add payment targets button to profile icon row

Shows a wallet icon button in the profile action row when a user has
published payment targets (kind 10133). Tapping it opens a dropdown
listing each target; selecting one opens the payto:// deep link.

https://claude.ai/code/session_018G4g1cChqjeNEM5TztD3FE

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/profile/header/PaymentButton.kt

@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.ui.screen.loggedIn.profile.header
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.width
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.outlined.AccountBalanceWallet
+import androidx.compose.material3.DropdownMenu
+import androidx.compose.material3.DropdownMenuItem
+import androidx.compose.material3.FilledTonalButton
+import androidx.compose.material3.Icon
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalUriHandler
+import androidx.compose.ui.unit.dp
+import com.vitorpamplona.amethyst.R
+import com.vitorpamplona.amethyst.model.User
+import com.vitorpamplona.amethyst.ui.note.LoadAddressableNote
+import com.vitorpamplona.amethyst.ui.screen.loggedIn.AccountViewModel
+import com.vitorpamplona.amethyst.ui.stringRes
+import com.vitorpamplona.amethyst.ui.theme.ZeroPadding
+import com.vitorpamplona.quartz.experimental.nipA3.PaymentTarget
+import com.vitorpamplona.quartz.experimental.nipA3.PaymentTargetsEvent
+
+@Composable
+fun PaymentButton(
+    user: User,
+    accountViewModel: AccountViewModel,
+) {
+    val address =
+        remember(user.pubkeyHex) {
+            PaymentTargetsEvent.createAddress(user.pubkeyHex)
+        }
+
+    LoadAddressableNote(address, accountViewModel) { note ->
+        val targets =
+            remember(note) {
+                (note?.event as? PaymentTargetsEvent)?.paymentTargets() ?: emptyList()
+            }
+        if (targets.isNotEmpty()) {
+            PaymentButtonWithTargets(targets)
+        }
+    }
+}
+
+@Composable
+fun PaymentButtonWithTargets(targets: List<PaymentTarget>) {
+    val uri = LocalUriHandler.current
+    var expanded by remember { mutableStateOf(false) }
+
+    Box {
+        FilledTonalButton(
+            modifier =
+                Modifier
+                    .padding(horizontal = 3.dp)
+                    .width(50.dp),
+            onClick = { expanded = true },
+            contentPadding = ZeroPadding,
+        ) {
+            Icon(
+                imageVector = Icons.Outlined.AccountBalanceWallet,
+                contentDescription = stringRes(R.string.payment_targets),
+            )
+        }
+
+        DropdownMenu(
+            expanded = expanded,
+            onDismissRequest = { expanded = false },
+        ) {
+            targets.forEach { target ->
+                DropdownMenuItem(
+                    text = {
+                        Text("${target.type.replaceFirstChar(Char::titlecase)}: ${target.authority}")
+                    },
+                    onClick = {
+                        expanded = false
+                        runCatching {
+                            uri.openUri("payto://${target.type}/${target.authority}")
+                        }
+                    },
+                )
+            }
+        }
+    }
+}

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/profile/header/ProfileActions.kt

@@ -40,6 +40,8 @@ fun ProfileActions(
 ) {
     MessageButton(baseUser, accountViewModel, nav)
 
+    PaymentButton(baseUser, accountViewModel)
+
     val isMe by
         remember(accountViewModel) { derivedStateOf { accountViewModel.userProfile() == baseUser } }