refactor(#5): convert SettingsScreen to use HermesScaffold

* refactor(#5): convert SettingsScreen to use HermesScaffold

Replace raw Material3 Scaffold + manual TopAppBar with the shared
HermesScaffold wrapper. Removes ~30 lines of duplicated boilerplate
and gives SettingsScreen scroll-aware top bar behavior.

Closes #5

* fix(#5): restore ExperimentalMaterial3Api import for SegmentedButton

---------

Co-authored-by: M57 <hy4ri@users.noreply.github.com>

app/src/main/java/com/m57/hermescontrol/ui/settings/SettingsScreen.kt

@@ -17,7 +17,6 @@ import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.text.KeyboardOptions
 import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.icons.Icons
-import androidx.compose.material.icons.automirrored.filled.ArrowBack
 import androidx.compose.material.icons.filled.Visibility
 import androidx.compose.material.icons.filled.VisibilityOff
 import androidx.compose.material3.Button
@@ -32,15 +31,12 @@ import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.OutlinedButton
 import androidx.compose.material3.OutlinedTextField
 import androidx.compose.material3.OutlinedTextFieldDefaults
-import androidx.compose.material3.Scaffold
 import androidx.compose.material3.SegmentedButton
 import androidx.compose.material3.SegmentedButtonDefaults
 import androidx.compose.material3.SingleChoiceSegmentedButtonRow
 import androidx.compose.material3.Switch
 import androidx.compose.material3.SwitchDefaults
 import androidx.compose.material3.Text
-import androidx.compose.material3.TopAppBar
-import androidx.compose.material3.TopAppBarDefaults
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
@@ -56,6 +52,7 @@ import androidx.compose.ui.unit.dp
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.m57.hermescontrol.theme.ThemePreference
+import com.m57.hermescontrol.ui.common.HermesScaffold
 
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
@@ -69,41 +66,17 @@ fun SettingsScreen(
 
     BackHandler(onBack = onBack)
 
-    Scaffold(
-        modifier = modifier.fillMaxSize(),
-        topBar = {
-            TopAppBar(
-                title = {
-                    Text(
-                        "Settings",
-                        style =
-                            MaterialTheme.typography.titleLarge.copy(
-                                fontWeight = FontWeight.Bold,
-                            ),
-                    )
-                },
-                navigationIcon = {
-                    IconButton(onClick = onBack) {
-                        Icon(
-                            imageVector = Icons.AutoMirrored.Filled.ArrowBack,
-                            contentDescription = "Back",
-                        )
-                    }
-                },
-                colors =
-                    TopAppBarDefaults.topAppBarColors(
-                        containerColor = MaterialTheme.colorScheme.surface,
-                    ),
-            )
-        },
-    ) { paddingValues ->
+    HermesScaffold(
+        title = "Settings",
+        showBack = true,
+        onBack = onBack,
+    ) {
         Column(
             modifier =
                 Modifier
                     .fillMaxSize()
-                    .padding(paddingValues)
                     .verticalScroll(rememberScrollState())
-                    .padding(16.dp),
+                    .padding(horizontal = 16.dp, vertical = 8.dp),
             verticalArrangement = Arrangement.spacedBy(16.dp),
         ) {
             // Connection section