Fix Dynamic List component layout settings persistence

• Restructured layout settings to use flat top-level properties
• Created proper CSS for Stack, Row, and Grid layouts with responsive behavior
• Added JavaScript toggle for layout-specific settings visibility
• Implemented proper settings form with containerized layout options
• Ensured settings are preserved when switching between layouts
• Improved Row layout to be single non-wrapping row with fixed-width items

🤖 Generated with Claude Code

Co-Authored-By: Claude noreply@anthropic.com