NEXUS POS Phase 19.10.11 — Bookshop Paystack POS Sandbox
Runtime 20261021.283 | Incremental requires installed runtime >= 20261021.282

For older production runtime 20261001.267, use the *CUMULATIVE PRODUCTION BRIDGE*.
Never lower the minimum runtime manually.

1. Back up production files, all client databases, and storage/security keys.
2. Upload the appropriate ZIP using Super Admin -> Updates.
3. Install and confirm the new runtime.
4. Configure ONLY merchant TEST credentials by shop under Bookshop Settings.
5. Set the public HTTPS sandbox webhook URL in the corresponding shop's
   Paystack TEST dashboard. localhost URLs cannot receive Paystack webhooks.
6. Test KSh 1-100 sandbox checkout with a limited-permission cashier.
7. Confirm no Sales / Stock / Registers / Profit entries are created.

Production HTTPS is required for gateway credential setup; gateway secrets remain
server-side. LIVE CHARGES AND LIVE SALE POSTING ARE NOT ENABLED IN THIS PHASE.
