Auto-generated sitemap covering static pages + all blog posts.

Submitted once to Google Search Console + Bing Webmaster Tools, then they re-crawl periodically and auto-discover new blog posts on every process restart that ships fresh content/blog/*.md files.

Priorities are rough guidance, not hard rules — Google mostly ignores them but Bing still uses them as a tiebreaker. We mark the homepage at 1.0, blog index at 0.8, individual posts at 0.7, marketing pages at 0.6, legal at 0.3.