Code-review scenarios

Status: Outline. Rank production risk rather than collecting style preferences.

Start with the checkout flow.

Scenarios to add

• Tenant-scoped CRUD endpoint with broken object authorization
• Import job with unbounded memory and unsafe retries
• Eloquent API resource with hidden N+1 queries
• Cache wrapper with incomplete keys and unsafe locks
• Deployment migration incompatible with old workers
• Over-abstracted CRUD module whose boundaries add no value