Stable image URLs (post-signing removal) make page-level caching
safe again. Homepage, genre page, sitemap, and detail page now
revalidate on an interval instead of running Prisma on every hit.
Reader and search keep dynamic rendering (searchParams) but wrap
their Prisma queries in unstable_cache.
TTLs: home/genre/detail 5m, reader manga 5m, reader page meta 1h
(immutable), search 1m, sitemap 1h.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>