feat: persist complete multitheme palettes

src/lib/theme-settings.ts

@@ -0,0 +1,11 @@
+import { THEME_COLOR_KEYS, type ThemeColorKey, type ThemeMode, type ThemePreset } from "@/lib/theme-presets";
+
+export function settingKey(key: ThemeColorKey, mode: ThemeMode): string {
+  return mode === "light" ? key : `${key}_dark`;
+}
+
+export function presetSettings(preset: ThemePreset): Array<[string, string]> {
+  return (["light", "dark"] as const).flatMap((mode) =>
+    THEME_COLOR_KEYS.map((key) => [settingKey(key, mode), preset[mode][key]] as [string, string]),
+  );
+}