fix: importing settings causes loss of the expected imported values

Author: shamim-emon

core/preference/impl/src/commonMain/kotlin/net/thunderbird/core/preference/display/visualSettings/DefaultDisplayVisualSettingsPreferenceManager.kt

@@ -15,6 +15,8 @@ import kotlinx.coroutines.launch
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
 import net.thunderbird.core.logging.Logger
+import net.thunderbird.core.preference.PreferenceChangeBroker
+import net.thunderbird.core.preference.PreferenceChangeSubscriber
 import net.thunderbird.core.preference.display.visualSettings.message.list.MessageListPreferencesManager
 import net.thunderbird.core.preference.storage.Storage
 import net.thunderbird.core.preference.storage.StorageEditor
@@ -28,10 +30,15 @@ class DefaultDisplayVisualSettingsPreferenceManager(
     private val logger: Logger,
     private val storagePersister: StoragePersister,
     private val storageEditor: StorageEditor,
+    preferenceChangeBroker: PreferenceChangeBroker,
     private val messageListPreferences: MessageListPreferencesManager,
     private val ioDispatcher: CoroutineDispatcher = Dispatchers.IO,
     private val scope: CoroutineScope = CoroutineScope(SupervisorJob()),
-) : DisplayVisualSettingsPreferenceManager {
+) : DisplayVisualSettingsPreferenceManager, PreferenceChangeSubscriber {
+
+    init {
+        preferenceChangeBroker.subscribe(this)
+    }
     private val internalConfigState = MutableStateFlow(value = loadConfig())
     private val configState: StateFlow<DisplayVisualSettings> = combine(
         internalConfigState,
@@ -95,4 +102,8 @@ class DefaultDisplayVisualSettingsPreferenceManager(
     override fun getConfig() = configState.value
 
     override fun getConfigFlow(): Flow<DisplayVisualSettings> = configState
+
+    override fun receive() {
+        internalConfigState.update { loadConfig() }
+    }
 }