AI Features updates

[ric-v]

This pull request updates documentation and UI to better showcase PgStudio's AI features, improve usability, and add troubleshooting resources. The most notable changes include a major rewrite and expansion of the AI capabilities section in the README.md, a new improvement roadmap, a comprehensive troubleshooting guide, and significant enhancements to the website's design and feature descriptions.

AI Features & Documentation Improvements

• Expanded and clarified AI capabilities in README.md, detailing features like query generation, optimization, data analysis, error handling, and safe execution. Added feature comparison table and unique PgStudio highlights. [1] [2] [3]
• Added a new docs/ROADMAP.md outlining completed phases, ongoing architectural refactoring, future features, and technical debt priorities.

Website & UI Enhancements

• Improved feature descriptions and badges in docs/index.html, highlighting unified toolkit, AI-powered chat, context-aware suggestions, and new AI capabilities like "Send to Chat" and "Custom Instructions". [1] [2] [3]
• Updated navigation, install buttons, and branding for clarity and consistency. [1] [2] [3] [4]

Troubleshooting & Comparison Resources

• Added detailed troubleshooting section to README.md for connection, performance, and error messages.
• Included a feature comparison table against pgAdmin, DBeaver, and TablePlus.

Visual & UX Refinements

• Redesigned AI capabilities section in docs/styles.css for better responsiveness, modern look, and improved hover effects.
• Enhanced feature highlight cards and badges for improved visibility and user engagement. [1] [2]

These changes collectively make PgStudio's documentation and website more informative, visually appealing, and user-friendly, with a strong focus on AI-powered features and practical troubleshooting.