This PR launches the DevFlow marketing site

[craigcallen]

Summary

This PR launches the DevFlow marketing site on main from feature/mcp-token-feature. It introduces the new Vite/React/Tailwind landing page, waitlist capture and deployment infrastructure, then follows with messaging, SEO, iconography, and responsive polish to make the site production-ready.

Changes

• Build the DevFlow marketing site with the full landing page experience, Framer Motion interactions, and Resend-backed waitlist signup
• Add S3 + CloudFront deployment via GitHub Actions, following the existing craigcallen.com PR-build and main-deploy pattern
• Improve search visibility with meta tags, structured data, sitemap, and robots.txt
• Rebrand the site with updated typography, colors, assets, and Font Awesome icons
• Rewrite the README as a product-facing landing page and point site GitHub navigation to the product README
• Refine marketing copy and section flow to better emphasize workflow, skills, and MCP's zero-context advantage
• Simplify the waitlist Lambda by removing CORS handling
• Fix animation config typing and resolve hero overflow issues on narrow layouts
• Align browser theming and responsive behavior for a more polished mobile experience

Test Notes

• Verify the marketing site renders correctly across desktop and narrow/mobile layouts
• Confirm waitlist signup still works end-to-end with the Lambda function URL
• Validate GitHub links, SEO artifacts, and deploy workflow behavior on PRs and main pushes