feat: name the host relay on Buzz notification cards

A Buzz/NIP-29 group id is only unique within its host relay, so a message
notification titled just "#general" doesn't say which #general it came from.
The Notifications card already draws a RelayGroupChannelHeader naming the
channel; add the relay next to it, mirroring what a Concord message gets on
the same cards (ConcordCommunityPill naming its parent community) and what the
Messages row already does for these groups.

Extracts the relay chip out of ChatroomHeaderCompose into a shared
RelayNameChip so the Messages row and the Notifications feed render the same
chip, the way ConcordCommunityPill is already shared between them. The chip
taps through to the relay's channel list; the name/avatar still open the room.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018DsoLSb42C3CdjMceJW2Pq

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/note/types/RelayGroupMessage.kt

@@ -49,13 +49,16 @@ import com.vitorpamplona.amethyst.model.Note
 import com.vitorpamplona.amethyst.service.relayClient.reqCommand.user.observeUserName
 import com.vitorpamplona.amethyst.ui.components.RobohashFallbackAsyncImage
 import com.vitorpamplona.amethyst.ui.navigation.navs.INav
+import com.vitorpamplona.amethyst.ui.navigation.routes.Route
 import com.vitorpamplona.amethyst.ui.navigation.routes.routeFor
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.AccountViewModel
+import com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.publicChannels.relayGroup.RelayNameChip
 import com.vitorpamplona.amethyst.ui.theme.StdVertSpacer
 import com.vitorpamplona.amethyst.ui.theme.replyModifier
 import com.vitorpamplona.quartz.buzz.workspace.buzzParticipants
 import com.vitorpamplona.quartz.buzz.workspace.isBuzzDm
 import com.vitorpamplona.quartz.nip01Core.core.HexKey
+import com.vitorpamplona.quartz.nip01Core.relay.normalizer.displayUrl
 import com.vitorpamplona.quartz.nipC7Chats.ChatEvent
 
 /**
@@ -100,7 +103,14 @@ fun RenderRelayGroupMessage(
     }
 }
 
-/** A compact, tappable header naming the Buzz group (or DM participant) a message belongs to. */
+/**
+ * A compact, tappable header naming the Buzz group (or DM participant) a message belongs to, plus a
+ * [RelayNameChip] naming its host relay — the same pairing the Messages row uses, and the NIP-29
+ * analog of the [com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.publicChannels.concord.ConcordCommunityPill]
+ * a Concord message wears on these same cards. A group id is only unique within its host relay, so
+ * without the relay a notification from `#general` doesn't say *which* `#general` it came from. The
+ * chip taps through to the relay's channel list, while the name/avatar open the room itself.
+ */
 @Composable
 fun RelayGroupChannelHeader(
     channel: RelayGroupChannel,
@@ -129,16 +139,21 @@ fun RelayGroupChannelHeader(
         )
 
         if (dmOther != null) {
-            RelayGroupDmName(dmOther, channel, accountViewModel, Modifier.weight(1f))
+            RelayGroupDmName(dmOther, channel, accountViewModel, Modifier.weight(1f, fill = false))
         } else {
             Text(
                 text = channel.toBestDisplayName(),
                 fontWeight = FontWeight.Bold,
                 maxLines = 1,
                 overflow = TextOverflow.Ellipsis,
-                modifier = Modifier.weight(1f),
+                modifier = Modifier.weight(1f, fill = false),
             )
         }
+
+        RelayNameChip(
+            label = channel.groupId.relayUrl.displayUrl(),
+            onClick = { nav.nav(Route.RelayGroupServer(channel.groupId.relayUrl.url)) },
+        )
     }
 }
 

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/chats/publicChannels/relayGroup/RelayNameChip.kt

@@ -0,0 +1,85 @@
+/*
+ * 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.chats.publicChannels.relayGroup
+
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.widthIn
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+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.ui.theme.ChatLabelMaxWidth
+
+/**
+ * A tappable chip naming the relay a NIP-29 / Buzz group lives on. A group id is only unique within
+ * its host relay, so the relay is part of the room's identity — the same `#general` can exist on two
+ * Buzz servers and only this chip tells them apart.
+ *
+ * Wears the same highlighted wash as [com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.publicChannels.concord.ConcordCommunityPill]
+ * so every "which server / community does this room belong to" chip reads the same way. Unlike the
+ * muted note-header [com.vitorpamplona.amethyst.commons.ui.note.HeaderPill] (PoW/OTS/location
+ * markers), this one is a first-class navigation entry point, so it keeps the stronger
+ * `secondaryContainer` highlight. Shared by the Messages row and the Notifications feed so a Buzz
+ * message reads the same wherever it surfaces; the width is capped at [ChatLabelMaxWidth] with a
+ * middle ellipsis so a long host is truncated instead of crowding the channel name out.
+ */
+@Composable
+fun RelayNameChip(
+    label: String,
+    onClick: () -> Unit,
+) {
+    Surface(
+        shape = RoundedCornerShape(6.dp),
+        color = MaterialTheme.colorScheme.secondaryContainer,
+        modifier = Modifier.widthIn(max = ChatLabelMaxWidth).clickable(onClick = onClick),
+    ) {
+        Row(
+            verticalAlignment = Alignment.CenterVertically,
+            horizontalArrangement = Arrangement.spacedBy(3.dp),
+            modifier = Modifier.padding(horizontal = 6.dp, vertical = 2.dp),
+        ) {
+            Icon(
+                symbol = MaterialSymbols.Dns,
+                contentDescription = null,
+                tint = MaterialTheme.colorScheme.onSecondaryContainer,
+                modifier = Modifier.size(11.dp),
+            )
+            Text(
+                text = label,
+                style = MaterialTheme.typography.labelSmall,
+                color = MaterialTheme.colorScheme.onSecondaryContainer,
+                maxLines = 1,
+                overflow = TextOverflow.MiddleEllipsis,
+            )
+        }
+    }
+}

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/chats/rooms/ChatroomHeaderCompose.kt

@@ -20,22 +20,16 @@
  */
 package com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.rooms
 
-import androidx.compose.foundation.clickable
-import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.RowScope
 import androidx.compose.foundation.layout.Spacer
-import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.layout.widthIn
-import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material3.DropdownMenu
 import androidx.compose.material3.DropdownMenuItem
 import androidx.compose.material3.LocalTextStyle
 import androidx.compose.material3.MaterialTheme
-import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
@@ -98,6 +92,7 @@ import com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.publicChannels.concor
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.publicChannels.concord.concordCommunityHasUnreadFlow
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.publicChannels.concord.rememberConcordImageModel
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.publicChannels.ephemChat.LoadEphemeralChatChannel
+import com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.publicChannels.relayGroup.RelayNameChip
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.publicChannels.relayGroup.relayGroupChannelLastReadRoute
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.publicChannels.relayGroup.relayGroupServerHasUnreadFlow
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.chats.rooms.dal.ConcordServerRoomNote
@@ -746,43 +741,6 @@ private fun ConcordServerRoomCompose(
     )
 }
 
-/**
- * A tappable chip naming the server/community a Messages row belongs to. Unlike the muted
- * note-header [HeaderPill] (PoW/OTS/location markers), this one is a first-class navigation entry
- * point, so it keeps the stronger `secondaryContainer` highlight.
- */
-@Composable
-private fun RelayNameChip(
-    label: String,
-    onClick: () -> Unit,
-) {
-    Surface(
-        shape = RoundedCornerShape(6.dp),
-        color = MaterialTheme.colorScheme.secondaryContainer,
-        modifier = Modifier.widthIn(max = ChatLabelMaxWidth).clickable(onClick = onClick),
-    ) {
-        Row(
-            verticalAlignment = Alignment.CenterVertically,
-            horizontalArrangement = Arrangement.spacedBy(3.dp),
-            modifier = Modifier.padding(horizontal = 6.dp, vertical = 2.dp),
-        ) {
-            Icon(
-                symbol = MaterialSymbols.Dns,
-                contentDescription = null,
-                tint = MaterialTheme.colorScheme.onSecondaryContainer,
-                modifier = Modifier.size(11.dp),
-            )
-            Text(
-                text = label,
-                style = MaterialTheme.typography.labelSmall,
-                color = MaterialTheme.colorScheme.onSecondaryContainer,
-                maxLines = 1,
-                overflow = TextOverflow.MiddleEllipsis,
-            )
-        }
-    }
-}
-
 /**
  * Renders a Messages row title as the channel name followed by a muted [HeaderPill] naming the room
  * type (Public Chat, Marmot Group, ...). The pill mirrors the Concord community chip so every group