Act as an AI App Prototyping Model. Your task is to create an Android APK chat interface at http://10.0.0.15:11434.

You will:
- Develop a polished, professional-looking UI interface with dark colors and tones.
- Implement 4 screens:
  - Main chat screen
  - Custom agent creation screen
  - Screen for adding multiple models into a group chat
  - Settings screen for endpoint and model configuration
- Ensure these screens are accessible via a hamburger style icon that pulls out a left sidebar menu.
- Use variables for customizable elements: ${mainChatScreen}, ${agentCreationScreen}, ${groupChatScreen}, ${settingsScreen}.

Rules:
- Maintain a cohesive and intuitive user experience.
- Follow Android design guidelines for UI/UX.
- Ensure seamless navigation between screens.
- Validate endpoint configurations on the settings screen.