List locally stored artifacts on the ChatRoomDetailScreen

The Library section hardcoded "No artifacts exists". Load and render the
chat room's stored artifacts instead.

- MantraArtifactDao.getArtifactsByChatRoomId + MantraRepository.getArtifacts
  expose a chat room's artifacts (newest first).
- ChatRoomDetailUIState.Loaded carries artifacts; ChatRoomDetailViewModel
  gains mantraRepository and loads them in initiateChatRoomDetail.
- ChatRoomDetailScreen renders the empty-state text only when there are no
  artifacts, otherwise a Card/ListItem per artifact (name, url, chevron to a
  pending detail route). The screen takes mantraRepository, threaded through
  the factory, the nav host (databaseMantraRepository), and the preview.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

composeApp/src/commonMain/kotlin/press/mantra/compose/database/dao/MantraArtifactDao.kt

@@ -1,6 +1,7 @@
 package press.mantra.compose.database.dao
 
 import androidx.room3.Dao
+import androidx.room3.Query
 import androidx.room3.Upsert
 import press.mantra.compose.database.model.MantraArtifact
 
@@ -8,4 +9,7 @@ import press.mantra.compose.database.model.MantraArtifact
 interface MantraArtifactDao {
     @Upsert
     suspend fun upsert(mantraArtifact: MantraArtifact)
+
+    @Query("SELECT * FROM MantraArtifact WHERE chatRoomId = :chatRoomId ORDER BY createdAt DESC")
+    suspend fun getArtifactsByChatRoomId(chatRoomId: String): List<MantraArtifact>
 }

composeApp/src/commonMain/kotlin/press/mantra/compose/database/repository/DatabaseMantraRepository.kt

@@ -21,6 +21,9 @@ class DatabaseMantraRepository(
 
     private val logger = Logger.withTag(TAG)
 
+    override suspend fun getArtifacts(chatRoomId: String): List<MantraArtifact> =
+        database.mantraArtifactDao().getArtifactsByChatRoomId(chatRoomId)
+
     override suspend fun getDialects(chatRoomId: String): List<MantraDialect> =
         database.mantraDialectDao().getDialectsByChatRoomId(chatRoomId)
 

composeApp/src/commonMain/kotlin/press/mantra/compose/repository/MantraRepository.kt

@@ -1,10 +1,13 @@
 package press.mantra.compose.repository
 
 import com.vitorpamplona.quartz.nip01Core.core.HexKey
+import press.mantra.compose.database.model.MantraArtifact
 import press.mantra.compose.database.model.MantraDialect
 import press.mantra.compose.database.model.MarmotInnerEvent
 
 interface MantraRepository {
+    suspend fun getArtifacts(chatRoomId: String): List<MantraArtifact>
+
     suspend fun getDialects(chatRoomId: String): List<MantraDialect>
 
     suspend fun addDialect(
@@ -38,6 +41,8 @@ interface MantraRepository {
         const val DEFAULT_LICENSE = "cc"
 
         val NO_OP_MANTRA_REPOSITORY = object: MantraRepository{
+            override suspend fun getArtifacts(chatRoomId: String): List<MantraArtifact> = emptyList()
+
             override suspend fun getDialects(chatRoomId: String): List<MantraDialect> = emptyList()
 
             override suspend fun addDialect(

composeApp/src/commonMain/kotlin/press/mantra/compose/ui/composable/ChatRoomDetailScreen.kt

@@ -46,6 +46,7 @@ import press.mantra.compose.database.model.Profile
 import press.mantra.compose.database.model.intermdiate.LocalChatRoom
 import press.mantra.compose.database.model.intermdiate.LocalParticipant
 import press.mantra.compose.repository.ChatRepository
+import press.mantra.compose.repository.MantraRepository
 import press.mantra.compose.repository.NostrRepository
 import press.mantra.compose.ui.composable.navigation.routes.ImplementationPendingRoute
 import press.mantra.compose.ui.composable.navigation.routes.Route
@@ -67,6 +68,7 @@ fun ChatRoomDetailScreen(
     initialChatRoomDetailUIState: ChatRoomDetailUIState = ChatRoomDetailUIState.Loading,
     nostrRepository: NostrRepository,
     chatRepository: ChatRepository,
+    mantraRepository: MantraRepository,
     onNavigateToRoute: (Route) -> Unit,
     onPopBackToRoute: (Route) -> Unit
 ) {
@@ -77,6 +79,7 @@ fun ChatRoomDetailScreen(
             initialChatRoomDetailUIState = initialChatRoomDetailUIState,
             nostrRepository = nostrRepository,
             chatRepository = chatRepository,
+            mantraRepository = mantraRepository,
             activeUserPublicKey = activeUserPublicKey
         )
     )
@@ -135,8 +138,46 @@ fun ChatRoomDetailScreen(
                             )
                         }
 
-                        item {
-                            Text("No artifacts exists in this groups library.")
+                        if (chatRoomDetailUIState.artifacts.isEmpty()) {
+                            item {
+                                Text("No artifacts exists in this groups library.")
+                            }
+                        } else {
+                            items(
+                                items = chatRoomDetailUIState.artifacts,
+                                key = { artifact -> artifact.id }
+                            ) { artifact ->
+                                Card(
+                                    onClick = {
+                                        onNavigateToRoute.invoke(
+                                            ImplementationPendingRoute(
+                                                "Artifact detail"
+                                            )
+                                        )
+                                    }
+                                ) {
+                                    ListItem(
+                                        leadingContent = {
+                                            Icon(
+                                                Icons.Default.LibraryBooks,
+                                                contentDescription = "Artifact"
+                                            )
+                                        },
+                                        trailingContent = {
+                                            Icon(
+                                                Icons.Default.ChevronRight,
+                                                contentDescription = "View artifact"
+                                            )
+                                        },
+                                        headlineContent = {
+                                            Text(text = artifact.name)
+                                        },
+                                        supportingContent = {
+                                            Text(text = artifact.url)
+                                        }
+                                    )
+                                }
+                            }
                         }
 
                         item {
@@ -435,6 +476,7 @@ private fun ChatRoomMessagingScreenPreview() {
                 ),
                 nostrRepository = NostrRepository.NO_OP_NOSTR_REPOSITORY,
                 chatRepository = ChatRepository.NO_OP_CHAT_REPOSITORY,
+                mantraRepository = MantraRepository.NO_OP_MANTRA_REPOSITORY,
                 onNavigateToRoute = {},
                 onPopBackToRoute = {}
             )

composeApp/src/commonMain/kotlin/press/mantra/compose/ui/composable/navigation/MantraNavHost.kt

@@ -597,6 +597,7 @@ fun MantraNavHost(
                 relayHint = route.relayHint,
                 nostrRepository = databaseNostrRepository,
                 chatRepository = databaseChatRepository,
+                mantraRepository = databaseMantraRepository,
                 onNavigateToRoute = { actionRoute ->
                     navController.navigate(
                         route = actionRoute

composeApp/src/commonMain/kotlin/press/mantra/compose/ui/view/model/ChatRoomDetailViewModel.kt

@@ -11,6 +11,7 @@ import androidx.lifecycle.viewmodel.initializer
 import androidx.lifecycle.viewmodel.viewModelFactory
 import press.mantra.compose.database.model.intermdiate.LocalChatRoom
 import press.mantra.compose.repository.ChatRepository
+import press.mantra.compose.repository.MantraRepository
 import press.mantra.compose.repository.NostrRepository
 import press.mantra.compose.ui.composable.navigation.routes.HomeRoute
 import press.mantra.compose.ui.composable.navigation.routes.Route
@@ -27,7 +28,8 @@ class ChatRoomDetailViewModel(
     val relayHint: String?,
     initialChatRoomDetailUIState: ChatRoomDetailUIState,
     val nostrRepository: NostrRepository,
-    val chatRepository: ChatRepository
+    val chatRepository: ChatRepository,
+    val mantraRepository: MantraRepository,
 ): ViewModel() {
 
     var chatRoomDetailUIState: ChatRoomDetailUIState by mutableStateOf(initialChatRoomDetailUIState)
@@ -51,7 +53,8 @@ class ChatRoomDetailViewModel(
                 ChatRoomDetailUIState.Error("Missing chat room")
             } else {
                 ChatRoomDetailUIState.Loaded(
-                    localChatRoom = localChatRoom
+                    localChatRoom = localChatRoom,
+                    artifacts = mantraRepository.getArtifacts(chatRoomId),
                 )
             }
         }
@@ -107,7 +110,8 @@ class ChatRoomDetailViewModel(
             relayHint: String?,
             initialChatRoomDetailUIState: ChatRoomDetailUIState = ChatRoomDetailUIState.Loading,
             nostrRepository: NostrRepository,
-            chatRepository: ChatRepository
+            chatRepository: ChatRepository,
+            mantraRepository: MantraRepository,
         ): ViewModelProvider.Factory = viewModelFactory {
             initializer {
                 ChatRoomDetailViewModel(
@@ -116,7 +120,8 @@ class ChatRoomDetailViewModel(
                     relayHint = relayHint,
                     initialChatRoomDetailUIState = initialChatRoomDetailUIState,
                     nostrRepository = nostrRepository,
-                    chatRepository = chatRepository
+                    chatRepository = chatRepository,
+                    mantraRepository = mantraRepository,
                 )
             }
         }

composeApp/src/commonMain/kotlin/press/mantra/compose/ui/view/state/ChatRoomDetailUIState.kt

@@ -1,10 +1,12 @@
 package press.mantra.compose.ui.view.state
 
+import press.mantra.compose.database.model.MantraArtifact
 import press.mantra.compose.database.model.intermdiate.LocalChatRoom
 
 sealed interface ChatRoomDetailUIState {
     data class Loaded(
-        val localChatRoom: LocalChatRoom
+        val localChatRoom: LocalChatRoom,
+        val artifacts: List<MantraArtifact> = emptyList(),
     ): ChatRoomDetailUIState
 
     data class Error(