feat(ai): add production-ready OpenAI chat with contextual history

[salmanabdurrahman]

Summary

This pull request delivers production-ready OpenAI integration, enabling AI-powered chat, content generation, and chat history retrieval to support contextual and intelligent user interactions.

Changes

AI Integration

• Integrated OpenAI API for chat and content generation.
• Utilizes stable AI configuration suitable for production use.

Chat History

• Enabled chat history retrieval to maintain conversation context.
• Improves response relevance and overall user experience.

API Enhancements

• Finalized AI response structure for consistent usage across the application.
• Established a scalable AI foundation for future features.

Reason

This PR promotes a tested and stable AI integration to the main branch, providing a smarter and more contextual user experience while laying groundwork for future AI-driven enhancements.

Notes

• Ensure OpenAI API key is properly configured in production environment.
• Monitor AI usage and chat history size for performance and cost control.
• No breaking changes introduced.