Refactor: Remove unused class and update navigation

- Remove unused `DefaultButtonStyle` class.
- Update `OnboardingScreen` to remove import of deleted class.
- Update `SettingsScreen` logout navigation from "login/greeting" to "choose-platform".
- Add padding to the logout button in `SettingsScreen`.

app/src/main/java/chat/revolt/composables/generic/DefaultButtonStyle.kt

@@ -1,4 +0,0 @@
-package chat.revolt.composables.generic
-
-class DefaultButtonStyle {
-}

app/src/main/java/chat/revolt/screens/register/OnboardingScreen.kt

@@ -36,7 +36,6 @@ import androidx.navigation.compose.rememberNavController
 import chat.revolt.R
 import chat.revolt.api.routes.onboard.OnboardingCompletionBody
 import chat.revolt.api.routes.onboard.completeOnboarding
-import chat.revolt.composables.generic.DefaultButtonStyle
 import chat.revolt.composables.generic.FormTextField
 import chat.revolt.persistence.KVStorage
 import kotlinx.coroutines.launch

app/src/main/java/chat/revolt/screens/settings/SettingsScreen.kt

@@ -380,10 +380,11 @@ fun SettingsScreen(
                             }
                         },
                         modifier = Modifier
+                            .padding(bottom =92.dp)
                             .testTag("settings_view_logout")
                             .clickable {
                                 viewModel.logout()
-                                navController.navigate("login/greeting") {
+                                navController.navigate("choose-platform") {
                                     popUpTo("chat") {
                                         inclusive = true
                                     }