# TASK 6.1: Implement Staging-To-Curated Orchestration And Upstream Load-To-Staging Batch Resolution

## Summary

Implement the tenant-day `staging_to_curated` entry point and the ETL/Warehouse orchestration flow that starts one `staging -> curated` run for Brink order-centric targets.

This subtask turns the replay boundary from `TASK5.md` and the lifecycle contract from `TASK3.md` into a concrete execution path that resolves the upstream load-to-staging batch, reads the available staging-load inventory, and prepares curated target execution.

## Dependencies

- [TASK 3](./TASK3.md) - batch lifecycle, checkpoints, and failure packaging
- [TASK 5](./TASK5.md) - load to Redshift staging

## Files to Create

### 1. Staging-to-curated orchestration services

Create or finalize the services responsible for one tenant-day `staging_to_curated` execution.

Recommended logical services:

- `BrinkPosStagingToCuratedJobs`
- `BrinkPosLoadToStagingBatchResolver`
- `BrinkPosCuratedTransformOrchestrator`

## Required Behavior

- child staging-to-curated accepts a `BrinkPosStagingToCuratedJobInput`-style contract
- explicit `LoadToStagingBatchId` wins when provided
- otherwise the resolver loads the current successful `load_to_staging` batch for the same tenant-day key
- the upstream load-to-staging batch must be successful and replayable
- orchestration resolves required staging-table availability from persisted upstream batch metadata rather than from assumptions about the warehouse state alone
- the orchestration layer passes only upstream batch context and target execution inputs into the curated boundary

## Testing

### Unit tests

Add unit tests for:

- explicit upstream load-to-staging batch selection
- implicit upstream load-to-staging batch selection through current-state lookup
- rejection of failed or invalid upstream load-to-staging batches
- staging-inventory resolution from persisted batch metadata
- orchestration handoff from child job to curated execution

## Acceptance Criteria

- [x] Child staging-to-curated job entry exists
- [x] Upstream load-to-staging batch resolution exists for explicit and implicit selection paths
- [x] Failed or invalid upstream load-to-staging batches are rejected
- [x] Required staging inventory is resolved from persisted batch metadata
- [x] Unit tests cover upstream resolution and orchestration behavior

## Notes

- Keep this subtask focused on stage orchestration readiness.
- Do not implement dependency matrix or SQL execution here; those belong to later subtasks in `TASK 6`.