feat(app): pickers for agent key, kind, and persona model/provider/runtime

Replace raw-code text fields in the Buzz agent flows with pickers, matching
the workflow-definition picker and the app's existing people-typeahead.

- Agent Attestation "Agent public key": a single-agent people picker
  (name typeahead over the local user cache + removable chip), with
  npub/hex paste kept as the Enter escape hatch for keys that aren't
  contacts yet.
- Agent Attestation "Restrict to kind": an editable dropdown of common
  named kinds (1 Text note, 7 Reaction, …), free numeric entry preserved,
  with the resolved name shown as supporting text.
- Agent Persona edit "Model / Provider / Runtime": editable dropdowns of
  well-known values (claude-*, gpt-*, anthropic/openai/…, goose/…), free
  entry preserved since these stay free-form on the wire.
- New reusable EditableSuggestDropdown (BuzzOptionDropdown.kt) backing the
  open-ended pickers.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011mApqAbr8vkLC7gUDjavu6

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/buzz/AgentAttestationScreen.kt

@@ -20,50 +20,84 @@
  */
 package com.vitorpamplona.amethyst.ui.screen.loggedIn.buzz
 
+import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.foundation.text.KeyboardActions
 import androidx.compose.foundation.text.KeyboardOptions
 import androidx.compose.foundation.verticalScroll
 import androidx.compose.material3.Button
 import androidx.compose.material3.Card
+import androidx.compose.material3.InputChip
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.OutlinedButton
 import androidx.compose.material3.OutlinedTextField
 import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
 import androidx.compose.ui.platform.LocalClipboard
 import androidx.compose.ui.text.font.FontFamily
 import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.input.ImeAction
 import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
+import com.vitorpamplona.amethyst.commons.icons.symbols.Icon
+import com.vitorpamplona.amethyst.commons.icons.symbols.MaterialSymbols
+import com.vitorpamplona.amethyst.commons.model.User
 import com.vitorpamplona.amethyst.commons.model.buzz.BuzzHeldAttestations
+import com.vitorpamplona.amethyst.model.LocalCache
+import com.vitorpamplona.amethyst.service.relayClient.reqCommand.user.observeUserName
 import com.vitorpamplona.amethyst.ui.components.util.setText
 import com.vitorpamplona.amethyst.ui.navigation.navs.INav
 import com.vitorpamplona.amethyst.ui.navigation.topbars.TopBarWithBackButton
+import com.vitorpamplona.amethyst.ui.note.UserPicture
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.AccountViewModel
 import com.vitorpamplona.quartz.buzz.oaOwnerAttestation.AttestationConditions
 import com.vitorpamplona.quartz.buzz.oaOwnerAttestation.OwnerAttestation
+import com.vitorpamplona.quartz.nip01Core.core.HexKey
 import com.vitorpamplona.quartz.nip01Core.core.isValid
 import com.vitorpamplona.quartz.nip01Core.crypto.KeyPair
 import com.vitorpamplona.quartz.nip19Bech32.decodePublicKeyAsHexOrNull
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 import kotlinx.serialization.json.Json
 import kotlinx.serialization.json.jsonArray
 import kotlinx.serialization.json.jsonPrimitive
 
+// Common event kinds an agent might be restricted to — suggestions for the "Restrict to kind" field;
+// any 0–65535 is still accepted by free numeric entry.
+private val KIND_OPTIONS =
+    listOf(
+        DropdownOption("1", "1 · Text note"),
+        DropdownOption("7", "7 · Reaction"),
+        DropdownOption("9", "9 · Group chat message"),
+        DropdownOption("1111", "1111 · Comment"),
+        DropdownOption("30023", "30023 · Long-form article"),
+        DropdownOption("40002", "40002 · Buzz minichat message"),
+    )
+
+private val KIND_LABELS = KIND_OPTIONS.associate { it.value to it.label }
+
 /**
  * Owner-side NIP-OA attestation issuance. The owner signs a standalone commitment
  * ([OwnerAttestation]) authorizing an agent pubkey to publish under optional
@@ -106,7 +140,7 @@ fun AgentAttestationScreen(
             if (privKey == null) {
                 ReadOnlyKeyNotice()
             } else {
-                AttestationForm(ownerKey = keyPair)
+                AttestationForm(ownerKey = keyPair, accountViewModel = accountViewModel, nav = nav)
             }
         }
     }
@@ -246,11 +280,15 @@ private fun ReadOnlyKeyNotice() {
 }
 
 @Composable
-private fun AttestationForm(ownerKey: KeyPair) {
+private fun AttestationForm(
+    ownerKey: KeyPair,
+    accountViewModel: AccountViewModel,
+    nav: INav,
+) {
     val clipboard = LocalClipboard.current
     val scope = rememberCoroutineScope()
 
-    var agentInput by remember { mutableStateOf("") }
+    var selectedAgent by remember { mutableStateOf<HexKey?>(null) }
     var kindInput by remember { mutableStateOf("") }
     var afterInput by remember { mutableStateOf("") }
     var beforeInput by remember { mutableStateOf("") }
@@ -265,16 +303,23 @@ private fun AttestationForm(ownerKey: KeyPair) {
         color = MaterialTheme.colorScheme.onSurfaceVariant,
     )
 
-    OutlinedTextField(
-        value = agentInput,
-        onValueChange = {
-            agentInput = it
+    // #1: pick the agent by name from the local user cache — or paste an npub/hex for a key that
+    // isn't a contact yet (the common case for an external agent operator).
+    AgentKeyPicker(
+        selected = selectedAgent,
+        accountViewModel = accountViewModel,
+        nav = nav,
+        onSelect = {
+            selectedAgent = it
             error = null
             result = null
         },
-        label = { Text("Agent public key (npub or hex)") },
-        singleLine = true,
-        modifier = Modifier.fillMaxWidth(),
+        onClear = {
+            selectedAgent = null
+            error = null
+            result = null
+        },
+        onInvalidPaste = { error = "Invalid agent public key. Enter an npub or 64-char hex key." },
     )
 
     Text(
@@ -283,17 +328,18 @@ private fun AttestationForm(ownerKey: KeyPair) {
         color = MaterialTheme.colorScheme.onSurfaceVariant,
     )
 
-    OutlinedTextField(
+    // #3: kind is any 0–65535, but the common ones have names — offer them, keep free numeric entry.
+    EditableSuggestDropdown(
         value = kindInput,
         onValueChange = {
             kindInput = it.filter(Char::isDigit)
             error = null
             result = null
         },
-        label = { Text("Restrict to kind (0–65535)") },
-        singleLine = true,
+        label = "Restrict to kind (0–65535)",
+        options = KIND_OPTIONS,
         keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Number),
-        modifier = Modifier.fillMaxWidth(),
+        supportingText = KIND_LABELS[kindInput],
     )
 
     OutlinedTextField(
@@ -332,7 +378,8 @@ private fun AttestationForm(ownerKey: KeyPair) {
 
     Button(
         onClick = {
-            when (val outcome = buildAttestation(agentInput, kindInput, afterInput, beforeInput, ownerKey)) {
+            val agent = selectedAgent ?: return@Button
+            when (val outcome = buildAttestation(agent, kindInput, afterInput, beforeInput, ownerKey)) {
                 is AttestationOutcome.Failure -> {
                     error = outcome.message
                     result = null
@@ -343,7 +390,7 @@ private fun AttestationForm(ownerKey: KeyPair) {
                 }
             }
         },
-        enabled = agentInput.isNotBlank(),
+        enabled = selectedAgent != null,
         modifier = Modifier.fillMaxWidth(),
     ) {
         Text("Generate attestation")
@@ -357,6 +404,106 @@ private fun AttestationForm(ownerKey: KeyPair) {
     }
 }
 
+/**
+ * Single-agent people picker: once an agent is chosen it shows as a removable chip; otherwise a
+ * name typeahead over the local user cache with an npub/hex paste escape hatch (Enter accepts it).
+ * Mirrors the New-DM recipient picker so authorizing an agent stops being the one raw-key field.
+ */
+@Composable
+private fun AgentKeyPicker(
+    selected: HexKey?,
+    accountViewModel: AccountViewModel,
+    nav: INav,
+    onSelect: (HexKey) -> Unit,
+    onClear: () -> Unit,
+    onInvalidPaste: () -> Unit,
+) {
+    if (selected != null) {
+        AgentChip(selected, accountViewModel, nav, onClear)
+        return
+    }
+
+    var query by remember { mutableStateOf("") }
+    var suggestions by remember { mutableStateOf<List<HexKey>>(emptyList()) }
+
+    LaunchedEffect(query) {
+        if (query.isBlank()) {
+            suggestions = emptyList()
+            return@LaunchedEffect
+        }
+        delay(150)
+        suggestions =
+            withContext(Dispatchers.IO) {
+                LocalCache.findUsersStartingWith(query.trim(), accountViewModel.account).map { it.pubkeyHex }.take(8)
+            }
+    }
+
+    OutlinedTextField(
+        value = query,
+        onValueChange = { query = it },
+        label = { Text("Agent (search a name, or paste npub / hex)") },
+        leadingIcon = { Icon(symbol = MaterialSymbols.Search, contentDescription = null, modifier = Modifier.size(20.dp)) },
+        singleLine = true,
+        keyboardOptions = KeyboardOptions(imeAction = ImeAction.Done),
+        keyboardActions =
+            KeyboardActions(
+                onDone = {
+                    val hex = decodePublicKeyAsHexOrNull(query.trim())?.takeIf { it.isValid() }
+                    if (hex != null) onSelect(hex) else onInvalidPaste()
+                },
+            ),
+        modifier = Modifier.fillMaxWidth(),
+    )
+    // A plain Column (not LazyColumn) — this form lives inside a verticalScroll parent.
+    suggestions.forEach { hex ->
+        AgentSuggestionRow(hex, accountViewModel, nav) { onSelect(hex) }
+    }
+}
+
+/** One tappable agent search result — avatar + resolved name. */
+@Composable
+private fun AgentSuggestionRow(
+    hex: HexKey,
+    accountViewModel: AccountViewModel,
+    nav: INav,
+    onClick: () -> Unit,
+) {
+    val user: User = remember(hex) { LocalCache.getOrCreateUser(hex) }
+    val name by observeUserName(user, accountViewModel)
+    Row(
+        modifier =
+            Modifier
+                .fillMaxWidth()
+                .clip(RoundedCornerShape(8.dp))
+                .clickable(onClick = onClick)
+                .padding(vertical = 8.dp, horizontal = 4.dp),
+        verticalAlignment = Alignment.CenterVertically,
+        horizontalArrangement = Arrangement.spacedBy(12.dp),
+    ) {
+        UserPicture(hex, 34.dp, accountViewModel = accountViewModel, nav = nav)
+        Text(name, maxLines = 1, overflow = TextOverflow.Ellipsis, style = MaterialTheme.typography.bodyLarge)
+    }
+}
+
+/** The chosen agent as a removable chip — tapping the close affordance clears the selection. */
+@Composable
+private fun AgentChip(
+    hex: HexKey,
+    accountViewModel: AccountViewModel,
+    nav: INav,
+    onRemove: () -> Unit,
+) {
+    val user: User = remember(hex) { LocalCache.getOrCreateUser(hex) }
+    val name by observeUserName(user, accountViewModel)
+    InputChip(
+        selected = false,
+        onClick = onRemove,
+        label = { Text(name, maxLines = 1, overflow = TextOverflow.Ellipsis) },
+        avatar = { UserPicture(hex, 22.dp, accountViewModel = accountViewModel, nav = nav) },
+        trailingIcon = { Icon(symbol = MaterialSymbols.Close, contentDescription = "Change agent", modifier = Modifier.size(16.dp)) },
+    )
+}
+
 @Composable
 private fun AttestationResultCard(
     attestation: OwnerAttestation,

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/buzz/AgentPersonaEditScreen.kt

@@ -42,6 +42,28 @@ import com.vitorpamplona.amethyst.ui.navigation.navs.INav
 import com.vitorpamplona.amethyst.ui.navigation.topbars.TopBarWithBackButton
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.AccountViewModel
 
+// Well-known values for the persona's optional model / provider / runtime — suggestions only; any
+// string is still accepted (the fields are free-form both in NIP-AP and in Buzz's persona events).
+private val MODEL_OPTIONS =
+    listOf(
+        "claude-opus-4-8",
+        "claude-opus-4",
+        "claude-sonnet-4-5",
+        "claude-haiku-4-5",
+        "gpt-4o",
+        "gpt-4.1",
+        "o3",
+        "gemini-2.5-pro",
+        "gemini-2.5-flash",
+        "llama-3.3-70b",
+    ).map { DropdownOption(it) }
+
+private val PROVIDER_OPTIONS =
+    listOf("anthropic", "openai", "google", "groq", "openrouter", "ollama", "bedrock", "azure").map { DropdownOption(it) }
+
+private val RUNTIME_OPTIONS =
+    listOf("goose", "claude-code", "custom").map { DropdownOption(it) }
+
 /**
  * Create or edit a Buzz Agent Persona (NIP-AP `kind:30175`). [slug] null → a new persona;
  * otherwise edits the existing one (slug locked). Publishes to the workspace's Buzz relays
@@ -96,26 +118,25 @@ fun AgentPersonaEditScreen(
                 minLines = 3,
                 modifier = Modifier.fillMaxWidth(),
             )
-            OutlinedTextField(
+            // Model / provider / runtime are free-form strings upstream, but their real-world values
+            // are a small known set — offer them as suggestions while keeping free entry.
+            EditableSuggestDropdown(
                 value = state.model,
                 onValueChange = viewModel::onModelChange,
-                label = { Text("Model (optional)") },
-                singleLine = true,
-                modifier = Modifier.fillMaxWidth(),
+                label = "Model (optional)",
+                options = MODEL_OPTIONS,
             )
-            OutlinedTextField(
+            EditableSuggestDropdown(
                 value = state.provider,
                 onValueChange = viewModel::onProviderChange,
-                label = { Text("Provider (optional)") },
-                singleLine = true,
-                modifier = Modifier.fillMaxWidth(),
+                label = "Provider (optional)",
+                options = PROVIDER_OPTIONS,
             )
-            OutlinedTextField(
+            EditableSuggestDropdown(
                 value = state.runtime,
                 onValueChange = viewModel::onRuntimeChange,
-                label = { Text("Runtime (optional)") },
-                singleLine = true,
-                modifier = Modifier.fillMaxWidth(),
+                label = "Runtime (optional)",
+                options = RUNTIME_OPTIONS,
             )
             OutlinedTextField(
                 value = state.avatarUrl,

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/buzz/BuzzOptionDropdown.kt

@@ -0,0 +1,94 @@
+/*
+ * 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.buzz
+
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.material3.DropdownMenuItem
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.ExposedDropdownMenuBox
+import androidx.compose.material3.ExposedDropdownMenuDefaults
+import androidx.compose.material3.MenuAnchorType
+import androidx.compose.material3.OutlinedTextField
+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
+
+/** One suggested value for an [EditableSuggestDropdown] — its stored [value] and the [label] shown. */
+data class DropdownOption(
+    val value: String,
+    val label: String = value,
+) {
+    fun matches(query: String): Boolean = value.contains(query, ignoreCase = true) || label.contains(query, ignoreCase = true)
+}
+
+/**
+ * An editable text field that also offers a dropdown of known [options] — pick a suggestion or type
+ * any value (free entry is preserved). The menu narrows to options matching the current text. This
+ * is the "code → picker, but still open-ended" pattern for fields whose value set is well-known but
+ * not closed (model / provider / runtime names, common event kinds).
+ */
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun EditableSuggestDropdown(
+    value: String,
+    onValueChange: (String) -> Unit,
+    label: String,
+    options: List<DropdownOption>,
+    modifier: Modifier = Modifier,
+    keyboardOptions: KeyboardOptions = KeyboardOptions.Default,
+    supportingText: String? = null,
+) {
+    var expanded by remember { mutableStateOf(false) }
+    val filtered = remember(value, options) { if (value.isBlank()) options else options.filter { it.matches(value) } }
+    val showMenu = expanded && filtered.isNotEmpty()
+
+    ExposedDropdownMenuBox(expanded = showMenu, onExpandedChange = { expanded = it }) {
+        OutlinedTextField(
+            value = value,
+            onValueChange = {
+                onValueChange(it)
+                expanded = true
+            },
+            label = { Text(label) },
+            singleLine = true,
+            trailingIcon = { ExposedDropdownMenuDefaults.TrailingIcon(expanded = showMenu) },
+            keyboardOptions = keyboardOptions,
+            supportingText = supportingText?.let { { Text(it) } },
+            modifier = modifier.fillMaxWidth().menuAnchor(MenuAnchorType.PrimaryEditable),
+        )
+        ExposedDropdownMenu(expanded = showMenu, onDismissRequest = { expanded = false }) {
+            filtered.forEach { opt ->
+                DropdownMenuItem(
+                    text = { Text(opt.label) },
+                    onClick = {
+                        onValueChange(opt.value)
+                        expanded = false
+                    },
+                )
+            }
+        }
+    }
+}