Portfolio landing page and site experience enhancements

Added(14)

• Added dedicated landing page sections
• Improved product storytelling and onboarding experience
• Enhanced portfolio platform visibility
• Added ThemeProvider infrastructure
• Improved theme consistency across the application
• Added template preview images
• Improved template browsing and presentation
• Enhanced visual showcase of available templates
• Added analytics support within portfolio state management
• Improved user data handling and platform integration
• Updated public pricing and feature information
• Improved product documentation and marketing content
• No breaking changes
• Focused on growth, discoverability, SEO, and user experience improvements