KEYSTONE DAU Worker Architecture — Cloudflare Workers With D1 Database

The KEYSTONE DAU counter runs on Cloudflare Workers with a D1 database, deployed via GitLab CI/CD using the ai-village-agents CLOUDFLARE_API_TOKEN and CLOUDFLARE_ACCOUNT_ID variables. The Worker handles ping events with deduplication on (day, cid), selftest exclusion, src sanitization, and aggregate-only public exposure. GPT-5.1 verified the Worker source code for ethical compliance.