Fix performance issue by caching typing effect settings in ChatUiState (#329)

* Fix performance issue by caching typing effect settings in ChatUiState

- Moved `AuthManager.isTypingEffectEnabled()` and `AuthManager.getTypingEffectDelayMs()` out of `ChatScreen.kt` recomposition loops.
- Stored `typingEffectEnabled` and `typingEffectDelayMs` in `ChatUiState`.
- Added `refreshSettings()` to `ChatViewModel` to fetch settings upon initialization and on returning to the chat screen (ON_START).
- Prevents expensive EncryptedSharedPreferences XML decryption occurring on every message per token stream update.

Fixes #269

* Fix performance issue by caching typing effect settings in ChatUiState

- Moved `AuthManager.isTypingEffectEnabled()` and `AuthManager.getTypingEffectDelayMs()` out of `ChatScreen.kt` recomposition loops.
- Stored `typingEffectEnabled` and `typingEffectDelayMs` in `ChatUiState`.
- Added `refreshSettings()` to `ChatViewModel` to fetch settings upon initialization and on returning to the chat screen (ON_START).
- Prevents expensive EncryptedSharedPreferences XML decryption occurring on every message per token stream update.
- Fixed `ChatViewModelTest` missing mocks for `AuthManager.isTypingEffectEnabled()` and `AuthManager.getTypingEffectDelayMs()`.
- Fixed ktlint unused import and max line length violations.

Fixes #269

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatScreen.kt

@@ -104,7 +104,6 @@ import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.m57.hermescontrol.NavigationController
 import com.m57.hermescontrol.R
-import com.m57.hermescontrol.data.local.AuthManager
 import com.m57.hermescontrol.data.ws.ConnectionStatus
 import com.m57.hermescontrol.notification.NotificationHelper
 import com.m57.hermescontrol.theme.StatusRed
@@ -174,6 +173,7 @@ fun ChatScreen(
                     androidx.lifecycle.Lifecycle.Event.ON_START -> {
                         NotificationHelper.setAppForeground(context, true)
                         NotificationHelper.stop(context)
+                        viewModel.refreshSettings()
                         viewModel.refreshCurrentSession()
                     }
 
@@ -441,13 +441,15 @@ fun ChatScreen(
 
                         val isLastMessage = index == state.messages.lastIndex
                         val isAssistant = message.role == MessageRole.ASSISTANT
-                        val typingEnabled = AuthManager.isTypingEffectEnabled()
-                        val typingDelayMs = AuthManager.getTypingEffectDelayMs()
 
-                        if (typingEnabled && isLastMessage && isAssistant && lastAnimatedMessageId != message.id) {
+                        if (state.typingEffectEnabled &&
+                            isLastMessage &&
+                            isAssistant &&
+                            lastAnimatedMessageId != message.id
+                        ) {
                             StreamingBubbleWithTypingEffect(
                                 streaming = message,
-                                typingDelayMs = typingDelayMs,
+                                typingDelayMs = state.typingEffectDelayMs,
                                 isDark = isDark,
                                 onAnimationComplete = {
                                     lastAnimatedMessageId = message.id
@@ -466,13 +468,10 @@ fun ChatScreen(
                     // Streaming message — rendered separately for O(1) updates
                     state.streamingMessage?.let { streaming ->
                         item(key = "streaming-${streaming.id}") {
-                            val typingEnabled = AuthManager.isTypingEffectEnabled()
-                            val typingDelayMs = AuthManager.getTypingEffectDelayMs()
-
-                            if (typingEnabled && streaming.isStreaming) {
+                            if (state.typingEffectEnabled && streaming.isStreaming) {
                                 StreamingBubbleWithTypingEffect(
                                     streaming = streaming,
-                                    typingDelayMs = typingDelayMs,
+                                    typingDelayMs = state.typingEffectDelayMs,
                                     isDark = isDark,
                                 )
                             } else {

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatViewModel.kt

@@ -57,6 +57,9 @@ data class ChatUiState(
     val searchQuery: String = "",
     val searchMatchIndices: List<Int> = emptyList(),
     val currentSearchMatchIndex: Int = -1,
+    // Cached settings
+    val typingEffectEnabled: Boolean = true,
+    val typingEffectDelayMs: Int = 30,
 ) {
     /** Convenience — derived from [connectionStatus]. */
     val isConnected: Boolean get() = connectionStatus == ConnectionStatus.CONNECTED
@@ -118,6 +121,7 @@ class ChatViewModel(
         )
 
     init {
+        refreshSettings()
         connectWebSocket()
         viewModelScope.launch {
             wsClient.events.collect { event ->
@@ -860,6 +864,15 @@ class ChatViewModel(
         loadSessionMessages(sessionId)
     }
 
+    fun refreshSettings() {
+        _uiState.update { state ->
+            state.copy(
+                typingEffectEnabled = AuthManager.isTypingEffectEnabled(),
+                typingEffectDelayMs = AuthManager.getTypingEffectDelayMs(),
+            )
+        }
+    }
+
     fun switchSession(sessionId: String) {
         if (sessionId == _uiState.value.currentSessionId) return