fix: Pass isDarkTheme parameter to MainScreen and ChatDetailScreen for consistent theming

app/src/main/java/com/rosetta/messenger/MainActivity.kt

@@ -716,7 +716,8 @@ fun MainScreen(
                         onNavigateToChat = { forwardUser ->
                             // 📨 Forward: переход в выбранный чат с полными данными
                             selectedUser = forwardUser
-                        }
+                        },
+                        isDarkTheme = isDarkTheme
                 )
             }
         }

app/src/main/java/com/rosetta/messenger/ui/chats/ChatDetailScreen.kt

@@ -89,7 +89,8 @@ fun ChatDetailScreen(
         onUserProfileClick: (SearchUser) -> Unit = {},
         currentUserPublicKey: String,
         currentUserPrivateKey: String,
-        totalUnreadFromOthers: Int = 0
+        totalUnreadFromOthers: Int = 0,
+        isDarkTheme: Boolean
 ) {
         val viewModel: ChatViewModel = viewModel(key = "chat_${user.publicKey}")
         val context = LocalContext.current
@@ -100,7 +101,6 @@ fun ChatDetailScreen(
         val database = RosettaDatabase.getDatabase(context)
 
         // UI Theme
-        val isDarkTheme = androidx.compose.foundation.isSystemInDarkTheme()
         val backgroundColor = if (isDarkTheme) Color(0xFF1A1A1A) else Color(0xFFF2F2F7)
         val textColor = if (isDarkTheme) Color.White else Color.Black
         val secondaryTextColor = if (isDarkTheme) Color(0xFF8E8E93) else Color(0xFF8E8E93)