add backend readiness contract for publish prechecks
guard publish flow with explicit validation and version-aware checks
make publish behavior more predictable for clients and safer against stale state
add backend readiness contract for publish prechecks
add pricing diagnostics to explain publish-blocking conditions
make publish decisions more explicit and easier to debug for clients
add backend endpoint for publish readiness checks
enforce publish gate contract before version publication
make publish preconditions explicit and consistent for clients
standardize typed error responses across draft, pricing and publish endpoints
reduce contract drift between related flows
keep client-side handling more predictable and consistent
add optimistic concurrency guards via expected scheme version id
protect draft editor, pricing snapshot, remap and publish flows from stale mutations
protect version creation from stale current version state
keep backward compatibility with optional query guards
verify 409 conflict behavior for stale clients and 200 for valid flows
