Update README and localization files to remove "self-hosted" references

- Revised the README.md to simplify the description of Nexumi.
- Updated layout.tsx to reflect the change in the bot's description.
- Modified German and English localization files to remove "self-hosted" from the bot's description and terms of service.

apps/webui/src/app/layout.tsx

@@ -11,7 +11,7 @@ const inter = Inter({ subsets: ['latin'], variable: '--font-inter', display: 'sw
 
 export const metadata: Metadata = {
   title: 'Nexumi — Discord Bot',
-  description: 'Self-hosted Discord bot with dashboard, moderation, and community modules'
+  description: 'Discord bot with dashboard, moderation, and community modules'
 };
 
 export default async function RootLayout({ children }: { children: ReactNode }) {