Add sitemap.xml generation as a final pass in the index builder. The
sitemap covers all public pages: home, leaderboard, bots list, bot
profiles, matches list, featured replays, seasons, rivalries,
predictions, and docs.
- Add SiteURL config field (ACB_SITE_URL env var, defaults to
https://aicodebattle.com)
- Add generateSitemap() function with proper XML encoding
- Add SitemapURL and Sitemap types for XML marshaling
- Call generateSitemap() at the end of generateAllIndexes()
- Write sitemap.xml to output directory alongside leaderboard.json
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>