Added type definitions for Colors object in LaunchScreen module (facebook#50118)

Summary:
## Changelog:

[GENERAL] [ADDED] - Added type definitions for Colors object in LaunchScreen module to enhance code readability and type safety.

Pull Request resolved: facebook#50118

Reviewed By: NickGerleman

Differential Revision: D71491870

Pulled By: lunaleaps

fbshipit-source-id: 48205fb4d03098f9bea32c1c18c5b18deb4fd7f0

Author: qnnp-me

packages/react-native/types/modules/LaunchScreen.d.ts

@@ -12,7 +12,15 @@
 declare module 'react-native/Libraries/NewAppScreen' {
   export const Header: any;
   export const LearnMoreLinks: any;
-  export const Colors: any;
+  export const Colors: {
+    primary: string;
+    white: string;
+    lighter: string;
+    light: string;
+    dark: string;
+    darker: string;
+    black: string;
+  };
   export const DebugInstructions: any;
   export const ReloadInstructions: any;
 }