- Card link color bumped to accent-high for WCAG AA contrast ratio
- Caddyfile: immutable cache headers for hashed _astro/* assets
- robots.txt: move LLMs-Txt to comments (not a standard directive)
- OG images: auto-generated per page via astro-og-canvas with maritime
teal theme, wired through Starlight route data middleware
- Mermaid: request flow and parallel fetch diagrams on architecture page
- robots.txt: sitemap and llms.txt references for crawlers
