restructure signed_app into flat modules and bump gpui-native-kit

crates/signed_app/src/app/helpers.rs

@@ -0,0 +1,12 @@
+use gpui::App;
+use gpui_native_kit::theme::{ThemeVariant, follow_system, set_mode_override};
+use settings::{AppearanceMode, Settings};
+
+/// Applies the persisted light/dark/system preference to the kit theme.
+pub fn apply_appearance(settings: &Settings, cx: &mut App) {
+    match settings.appearance {
+        AppearanceMode::System => follow_system(cx),
+        AppearanceMode::Light => set_mode_override(Some(ThemeVariant::Light), cx),
+        AppearanceMode::Dark => set_mode_override(Some(ThemeVariant::Dark), cx),
+    }
+}