environment variable support and enhanced UI

[casistack]

UI Enhancements and Copy Functionality

Changes Made

1. Enhanced the research report interface with modern copy and export functionality

   • Added copy to clipboard with visual feedback
   • Added PDF export capability
   • Improved button styling and positioning

2. Improved input section layout and spacing

   • Increased text area height for better visibility
   • Added proper spacing and alignment for buttons
   • Enhanced visual feedback on input focus

3. Added modern styling touches

   • Consistent button sizes and spacing
   • Better visual hierarchy with proper margins
   • Improved card layouts with subtle borders
   • Added hover effects for better interactivity

Technical Details

• Implemented proper clipboard functionality using rx.set_clipboard
• Added success state animation for copy action
• Used proper Lucide icons throughout the interface
• Maintained existing functionality while adding new features
• Improved button positioning with proper spacing and alignment

Testing Done

• Verified copy functionality works correctly
• Confirmed PDF export opens in new window
• Tested responsive layout at different screen sizes
• Ensured all existing functionality remains intact