- Wire COOKIE_DOMAIN env var into BetterAuth cookie config - Add URL validation for TRUSTED_ORIGINS (rejects non-HTTP, invalid URLs) - Include original parse error in validateRedirectUri error message - Distinguish infrastructure errors from auth errors in verifySession (Prisma/connection errors now propagate as 500 instead of masking as 401) Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>