feat: add tag filter chips in Feed with popular tags LazyRow

FeedViewModel fetches tags on refresh(), takes top 10 by post count.
FeedScreen shows LazyRow of FilterChip below status filter: "All tags"
first, then popular tags with post counts. Tapping filters posts by tag.
Post cards now show tags in compact labelSmall format joined by dots.

app/src/main/java/com/swoosh/microblog/ui/feed/FeedScreen.kt

@@ -33,6 +33,7 @@ import androidx.compose.foundation.horizontalScroll
 import androidx.compose.foundation.layout.*
 import kotlinx.coroutines.launch
 import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.LazyRow
 import androidx.compose.foundation.lazy.items
 import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.foundation.pager.HorizontalPager
@@ -83,6 +84,7 @@ import com.swoosh.microblog.data.CredentialsManager
 import com.swoosh.microblog.data.ShareUtils
 import com.swoosh.microblog.data.model.FeedPost
 import com.swoosh.microblog.data.model.GhostAccount
+import com.swoosh.microblog.data.model.GhostTagFull
 import com.swoosh.microblog.data.model.PostFilter
 import com.swoosh.microblog.data.model.PostStats
 import com.swoosh.microblog.data.model.QueueStatus
@@ -109,6 +111,7 @@ fun FeedScreen(
     val recentSearches by viewModel.recentSearches.collectAsStateWithLifecycle()
     val accounts by viewModel.accounts.collectAsStateWithLifecycle()
     val activeAccount by viewModel.activeAccount.collectAsStateWithLifecycle()
+    val popularTags by viewModel.popularTags.collectAsStateWithLifecycle()
     val listState = rememberLazyListState()
     val context = LocalContext.current
     val snackbarHostState = remember { SnackbarHostState() }
@@ -305,20 +308,17 @@ fun FeedScreen(
                 )
             }
 
-            // Active tag filter bar
+            // Tag filter chips
-            if (state.activeTagFilter != null) {
+            AnimatedVisibility(
-                FilterChip(
+                visible = !isSearchActive && popularTags.isNotEmpty(),
-                    onClick = { viewModel.clearTagFilter() },
+                enter = fadeIn(SwooshMotion.quick()) + expandVertically(),
-                    label = { Text("#${state.activeTagFilter}") },
+                exit = fadeOut(SwooshMotion.quick()) + shrinkVertically()
-                    selected = true,
+            ) {
-                    leadingIcon = {
+                TagFilterChipsBar(
-                        Icon(Icons.Default.Tag, contentDescription = null, modifier = Modifier.size(16.dp))
+                    tags = popularTags,
-                    },
+                    activeTagFilter = state.activeTagFilter,
-                    trailingIcon = {
+                    onTagSelected = { viewModel.filterByTag(it) },
-                        Icon(Icons.Default.Close, contentDescription = "Clear filter", modifier = Modifier.size(16.dp))
+                    onClearFilter = { viewModel.clearTagFilter() }
-                    },
-                    modifier = Modifier
-                        .padding(horizontal = 16.dp, vertical = 4.dp)
                 )
             }
 
@@ -775,6 +775,58 @@ fun FilterChipsBar(
     }
 }
 
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun TagFilterChipsBar(
+    tags: List<GhostTagFull>,
+    activeTagFilter: String?,
+    onTagSelected: (String) -> Unit,
+    onClearFilter: () -> Unit
+) {
+    LazyRow(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(vertical = 4.dp),
+        contentPadding = PaddingValues(horizontal = 16.dp),
+        horizontalArrangement = Arrangement.spacedBy(8.dp)
+    ) {
+        // "All tags" chip
+        item {
+            val isAllSelected = activeTagFilter == null
+            FilterChip(
+                selected = isAllSelected,
+                onClick = { onClearFilter() },
+                label = { Text("All tags") },
+                colors = FilterChipDefaults.filterChipColors(
+                    selectedContainerColor = MaterialTheme.colorScheme.primaryContainer
+                )
+            )
+        }
+
+        // Tag chips
+        items(tags, key = { it.id ?: it.name }) { tag ->
+            val isSelected = activeTagFilter != null && activeTagFilter.equals(tag.name, ignoreCase = true)
+            FilterChip(
+                selected = isSelected,
+                onClick = {
+                    if (isSelected) onClearFilter() else onTagSelected(tag.name)
+                },
+                label = {
+                    val postCount = tag.count?.posts
+                    if (postCount != null) {
+                        Text("${tag.name} ($postCount)")
+                    } else {
+                        Text(tag.name)
+                    }
+                },
+                colors = FilterChipDefaults.filterChipColors(
+                    selectedContainerColor = MaterialTheme.colorScheme.primaryContainer
+                )
+            )
+        }
+    }
+}
+
 @Composable
 fun SortButton(
     currentSort: SortOrder,
@@ -1519,23 +1571,19 @@ fun PostCardContent(
                 }
             }
 
-            // Hashtag tags (bold colored text, not chips)
+            // Tags display
             if (post.tags.isNotEmpty()) {
                 Spacer(modifier = Modifier.height(10.dp))
-                @OptIn(ExperimentalLayoutApi::class)
+                Text(
-                FlowRow(
+                    text = post.tags.joinToString(" \u00B7 ") { "#$it" },
-                    horizontalArrangement = Arrangement.spacedBy(8.dp),
+                    style = MaterialTheme.typography.labelSmall,
-                    verticalArrangement = Arrangement.spacedBy(4.dp)
+                    color = MaterialTheme.colorScheme.primary,
-                ) {
+                    maxLines = 1,
-                    post.tags.forEach { tag ->
+                    overflow = TextOverflow.Ellipsis,
-                        Text(
+                    modifier = Modifier.clickable {
-                            text = "#$tag",
+                        post.tags.firstOrNull()?.let { onTagClick(it) }
-                            style = MaterialTheme.typography.labelMedium.copy(fontWeight = FontWeight.Bold),
-                            color = MaterialTheme.colorScheme.primary,
-                            modifier = Modifier.clickable { onTagClick(tag) }
-                        )
                     }
-                }
+                )
             }
 
             // Queue status

app/src/main/java/com/swoosh/microblog/ui/feed/FeedViewModel.kt

@@ -13,6 +13,7 @@ import com.swoosh.microblog.data.api.ApiClient
 import com.swoosh.microblog.data.db.Converters
 import com.swoosh.microblog.data.model.*
 import com.swoosh.microblog.data.repository.PostRepository
+import com.swoosh.microblog.data.repository.TagRepository
 import com.google.gson.Gson
 import com.google.gson.reflect.TypeToken
 import kotlinx.coroutines.FlowPreview
@@ -38,6 +39,7 @@ class FeedViewModel(application: Application) : AndroidViewModel(application) {
 
     private val accountManager = AccountManager(application)
     private var repository = PostRepository(application)
+    private var tagRepository = TagRepository(application)
     private val feedPreferences = FeedPreferences(application)
     private val searchHistoryManager = SearchHistoryManager(application)
 
@@ -71,6 +73,9 @@ class FeedViewModel(application: Application) : AndroidViewModel(application) {
     private val _recentSearches = MutableStateFlow<List<String>>(emptyList())
     val recentSearches: StateFlow<List<String>> = _recentSearches.asStateFlow()
 
+    private val _popularTags = MutableStateFlow<List<GhostTagFull>>(emptyList())
+    val popularTags: StateFlow<List<GhostTagFull>> = _popularTags.asStateFlow()
+
     private val _accounts = MutableStateFlow<List<GhostAccount>>(emptyList())
     val accounts: StateFlow<List<GhostAccount>> = _accounts.asStateFlow()
 
@@ -237,8 +242,9 @@ class FeedViewModel(application: Application) : AndroidViewModel(application) {
             accountManager.setActiveAccount(accountId)
             ApiClient.reset()
 
-            // Re-create repository to pick up new account
+            // Re-create repositories to pick up new account
             repository = PostRepository(getApplication())
+            tagRepository = TagRepository(getApplication())
 
             refreshAccountsList()
 
@@ -296,6 +302,18 @@ class FeedViewModel(application: Application) : AndroidViewModel(application) {
             val sort = _sortOrder.value
             val tagFilter = _uiState.value.activeTagFilter
 
+            // Fetch popular tags in parallel
+            launch {
+                tagRepository.fetchTags().fold(
+                    onSuccess = { tags ->
+                        _popularTags.value = tags
+                            .sortedByDescending { it.count?.posts ?: 0 }
+                            .take(10)
+                    },
+                    onFailure = { /* silently ignore tag fetch failures */ }
+                )
+            }
+
             repository.fetchPosts(page = 1, filter = filter, sortOrder = sort, tagFilter = tagFilter).fold(
                 onSuccess = { response ->
                     remotePosts = response.posts.map { it.toFeedPost() }