android: add floating bottom nav shell to chat list

android/app/src/main/java/ru/daemonlord/messenger/ui/chats/ChatListScreen.kt

@@ -25,6 +25,7 @@ import androidx.compose.material3.CircularProgressIndicator
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Surface
 import androidx.compose.material3.Tab
 import androidx.compose.material3.TabRow
 import androidx.compose.material3.Text
@@ -192,10 +193,27 @@ fun ChatListScreen(
                 onClick = {},
                 modifier = Modifier
                     .align(Alignment.BottomEnd)
-                    .padding(16.dp),
+                    .padding(end = 16.dp, bottom = 88.dp),
             ) {
                 Text("+")
             }
+            Surface(
+                modifier = Modifier
+                    .align(Alignment.BottomCenter)
+                    .padding(horizontal = 16.dp, vertical = 14.dp),
+                shape = CircleShape,
+                color = MaterialTheme.colorScheme.surfaceVariant.copy(alpha = 0.92f),
+            ) {
+                Row(
+                    modifier = Modifier.padding(horizontal = 12.dp, vertical = 8.dp),
+                    horizontalArrangement = Arrangement.spacedBy(8.dp),
+                ) {
+                    BottomNavPill(label = "Chats", selected = true, onClick = {})
+                    BottomNavPill(label = "Contacts", selected = false, onClick = {})
+                    BottomNavPill(label = "Settings", selected = false, onClick = {})
+                    BottomNavPill(label = "Profile", selected = false, onClick = {})
+                }
+            }
         }
     }
 }
@@ -363,6 +381,34 @@ private fun ArchiveRow(
     }
 }
 
+@Composable
+private fun BottomNavPill(
+    label: String,
+    selected: Boolean,
+    onClick: () -> Unit,
+) {
+    Surface(
+        shape = CircleShape,
+        color = if (selected) {
+            MaterialTheme.colorScheme.primaryContainer
+        } else {
+            MaterialTheme.colorScheme.surface
+        },
+        modifier = Modifier.clickable(onClick = onClick),
+    ) {
+        Text(
+            text = label,
+            modifier = Modifier.padding(horizontal = 10.dp, vertical = 6.dp),
+            style = MaterialTheme.typography.labelMedium,
+            color = if (selected) {
+                MaterialTheme.colorScheme.onPrimaryContainer
+            } else {
+                MaterialTheme.colorScheme.onSurface
+            },
+        )
+    }
+}
+
 @Composable
 private fun CenterState(
     text: String?,