separate smoke coverage into core backend checks and pricing publish flow checks
make regression runs more focused and easier to maintain
improve troubleshooting when a smoke stage fails
- add editor entry flow with editor context and ensure-draft bootstrap
- add draft summary read model and single-record draft read endpoints
- add typed draft, edit and publish conflicts with validation errors
- add pricing diagnostics and publish readiness endpoints
- fix Decimal serialization in seat price and test preview flows
- harden draft lifecycle guards for published vs draft current version
- update API map and smoke regression checklist
- add backend README and smoke regression script