Refactor: Extract RootScreen from MainActivity and fix reply message user

This commit refactors the UI composition logic by extracting it from `MainActivity` into a new, dedicated `RootScreen` composable. This improves the separation of concerns and simplifies `MainActivity`.

Additionally, a bug has been fixed where a replied-to message would incorrectly display the author of the parent message instead of its own author.

Key changes:
- Moved theme setup, permission handling, Long-Poll/Online service management, and navigation graph hosting into the new `RootScreen.kt`.
- `MainActivity` is now significantly simplified, delegating its UI composition to `RootScreen`.
- Corrected the user and group assignment for `replyMessage` in `MessagesRepositoryImpl` to ensure the correct author is displayed.
- Introduced `OnlineFriendsViewModel` to the `FriendsRoute` to separate the logic for online friends.
- Replaced `List` with a custom `ImmutableList` for `photoViewerInfo` state to improve Compose stability.

feature/friends/src/main/kotlin/dev/meloda/fast/friends/navigation/FriendsNavigation.kt

@@ -5,6 +5,7 @@ import androidx.navigation.NavGraphBuilder
 import androidx.navigation.compose.composable
 import dev.meloda.fast.friends.FriendsViewModel
 import dev.meloda.fast.friends.FriendsViewModelImpl
+import dev.meloda.fast.friends.OnlineFriendsViewModelImpl
 import dev.meloda.fast.friends.presentation.FriendsRoute
 import dev.meloda.fast.model.BaseError
 import kotlinx.serialization.Serializable
@@ -20,14 +21,14 @@ fun NavGraphBuilder.friendsScreen(
     onMessageClicked: (userId: Long) -> Unit,
     onScrolledToTop: () -> Unit
 ) {
-    val friendsViewModel: FriendsViewModel = with(activity) {
-        getViewModel<FriendsViewModelImpl>()
-    }
+    val friendsViewModel: FriendsViewModel = activity.getViewModel<FriendsViewModelImpl>()
+    val onlineFriendsViewModel =
+        activity.getViewModel<OnlineFriendsViewModelImpl>()
 
     composable<Friends> {
         FriendsRoute(
-            activity = activity,
             friendsViewModel = friendsViewModel,
+            onlineFriendsViewModel = onlineFriendsViewModel,
             onError = onError,
             onPhotoClicked = onPhotoClicked,
             onMessageClicked = onMessageClicked,

feature/friends/src/main/kotlin/dev/meloda/fast/friends/presentation/RootFriendsScreen.kt

@@ -1,6 +1,5 @@
 package dev.meloda.fast.friends.presentation
 
-import androidx.appcompat.app.AppCompatActivity
 import androidx.compose.animation.animateColorAsState
 import androidx.compose.animation.core.FastOutLinearInEasing
 import androidx.compose.animation.core.animateFloatAsState
@@ -54,17 +53,16 @@ import dev.meloda.fast.ui.theme.LocalHazeState
 import dev.meloda.fast.ui.theme.LocalThemeConfig
 import dev.meloda.fast.ui.util.ImmutableList
 import kotlinx.coroutines.launch
-import org.koin.androidx.viewmodel.ext.android.getViewModel
 
 @OptIn(ExperimentalMaterial3Api::class, ExperimentalHazeMaterialsApi::class)
 @Composable
 fun FriendsRoute(
-    activity: AppCompatActivity,
     friendsViewModel: FriendsViewModel,
+    onlineFriendsViewModel: OnlineFriendsViewModelImpl,
     onError: (BaseError) -> Unit,
     onPhotoClicked: (url: String) -> Unit,
     onMessageClicked: (userid: Long) -> Unit,
-    onScrolledToTop: () -> Unit
+    onScrolledToTop: () -> Unit,
 ) {
     val scope = rememberCoroutineScope()
     val currentTheme = LocalThemeConfig.current
@@ -232,9 +230,7 @@ fun FriendsRoute(
             modifier = Modifier.fillMaxSize(),
         ) { index ->
             FriendsScreen(
-                viewModel = if (index == 0) friendsViewModel else with(activity) {
-                    getViewModel<OnlineFriendsViewModelImpl>()
-                },
+                viewModel = if (index == 0) friendsViewModel else onlineFriendsViewModel,
                 orderType = orderType,
                 padding = padding,
                 tabIndex = index,