feat: add featured section, logo gallery, Firecrawl import, and API export

Featured Section
- Frontmatter-controlled featured items with featured: true and featuredOrder
- Card view with excerpts and list/card toggle button
- View preference saved to localStorage
- New Convex queries for featured posts and pages with by_featured index

Logo Gallery
- Continuous marquee scroll with clickable logos
- CSS animation, grayscale with color on hover
- Configurable speed, position, and title
- 5 sample logos included

Firecrawl Content Importer
- npm run import <url> scrapes external URLs to markdown drafts
- Creates local files in content/blog/ with frontmatter
- Then sync to dev or prod (no separate import:prod command)

API Enhancements
- New /api/export endpoint for batch content fetching
- AI plugin discovery at /.well-known/ai-plugin.json
- OpenAPI 3.0 spec at /openapi.yaml
- Enhanced llms.txt documentation

Documentation
- AGENTS.md with codebase instructions for AI agents
- Updated all sync vs deploy tables to include import workflow
- Renamed content/pages/changelog.md to changelog-page.md

Technical
- New components: FeaturedCards.tsx, LogoMarquee.tsx
- New script: scripts/import-url.ts
- New dependency: @mendable/firecrawl-js
- Schema updates with featured, featuredOrder, excerpt fields

netlify/edge-functions/api.ts

@@ -57,5 +57,5 @@ export default async function handler(
 }
 
 export const config = {
-  path: ["/api/posts", "/api/post"],
+  path: ["/api/posts", "/api/post", "/api/export"],
 };