Refactor: Extract boilerplate: safeLaunchLoad, clearToast, ToastEffect (CODE-21/22/23) (#312)

- Extracted `safeLaunchLoad` inline extension function to `ViewModelExt.kt` to encapsulate API call success/failure handling logic and replaced usages across 18 viewmodels.
- Extracted `ToastHost` interface to standardize `clearToast()` behavior across all ViewModels displaying toasts.
- Extracted `ToastEffect` composable to `SharedComponents.kt` and applied it to 16 screens, reducing repetitive side effect code blocks.

Fixes #286

app/src/main/java/com/m57/hermescontrol/ui/model/ModelScreen.kt

@@ -1,6 +1,5 @@
 package com.m57.hermescontrol.ui.model
 
-import android.widget.Toast
 import androidx.compose.animation.AnimatedVisibility
 import androidx.compose.foundation.BorderStroke
 import androidx.compose.foundation.layout.Arrangement
@@ -34,7 +33,6 @@ import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
-import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
@@ -46,6 +44,7 @@ import com.m57.hermescontrol.ui.common.ErrorState
 import com.m57.hermescontrol.ui.common.HermesScaffold
 import com.m57.hermescontrol.ui.common.LoadingState
 import com.m57.hermescontrol.ui.common.SearchBar
+import com.m57.hermescontrol.ui.common.ToastEffect
 
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
@@ -55,7 +54,6 @@ fun ModelScreen(
     viewModel: ModelViewModel = viewModel { ModelViewModel() },
 ) {
     val state by viewModel.uiState.collectAsStateWithLifecycle()
-    val context = LocalContext.current
     var expandedProviderSlug by remember { mutableStateOf<String?>(null) }
     var query by remember { mutableStateOf("") }
 
@@ -74,12 +72,7 @@ fun ModelScreen(
         viewModel.loadModelOptions()
     }
 
-    LaunchedEffect(state.toastMessage) {
-        state.toastMessage?.let { msg ->
-            Toast.makeText(context, msg, Toast.LENGTH_SHORT).show()
-            viewModel.clearToast()
-        }
-    }
+    ToastEffect(toastMessage = state.toastMessage, onClearToast = viewModel::clearToast)
 
     HermesScaffold(
         title = { Text(stringResource(R.string.screen_models)) },

app/src/main/java/com/m57/hermescontrol/ui/model/ModelViewModel.kt

@@ -8,6 +8,7 @@ import com.m57.hermescontrol.data.model.UpdateProfileModelRequest
 import com.m57.hermescontrol.data.remote.ApiClient
 import com.m57.hermescontrol.data.remote.NetworkResult
 import com.m57.hermescontrol.data.remote.safeApiCall
+import com.m57.hermescontrol.ui.common.ToastHost
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
@@ -24,7 +25,7 @@ data class ModelUiState(
     val toastMessage: String? = null,
 )
 
-class ModelViewModel : ViewModel() {
+class ModelViewModel : ViewModel(), ToastHost {
     private val _uiState = MutableStateFlow(ModelUiState())
     val uiState: StateFlow<ModelUiState> = _uiState.asStateFlow()
 
@@ -130,7 +131,7 @@ class ModelViewModel : ViewModel() {
         }
     }
 
-    fun clearToast() {
+    override fun clearToast() {
         _uiState.update { it.copy(toastMessage = null) }
     }
 }