Add settings for custom backgrounds and allow users to set image and video backgrounds

src/types/storage.ts

@@ -1,6 +1,6 @@
 export interface SettingsState {
   DarkMode: boolean;
-  theme: string;
+  selectedTheme: string;
   animatedbk: boolean;
   bksliderinput: string;
   customshortcuts: CustomShortcut[];