# TASK 1.1: Create Tenant Routing Metadata in kdsaidb

## Summary

Create the minimal operational metadata needed to support tenant-aware Redshift routing in `kdsaidb`.

This task establishes the service-owned metadata model for:

- tenant warehouse mapping,
- ingestion batch skeleton,
- checkpoint skeleton.

It also establishes the first explicit administrative operation for the new warehouse foundation: tenant registration in metadata.

The registration step should create more than a bare key-value mapping. It should persist lightweight control-plane metadata that later admin/API onboarding can reuse.

Registration should be idempotent where possible, but it should not activate the tenant warehouse yet.

This is a foundation task. It is not the final ETL runtime model.

## Dependencies

- None (first task)

## Files to Create

### 1. Metadata entities/configurations/migration files in `backend/Kds.Ai.Data`

Create the entity and EF configuration set needed to persist:

- tenant warehouse mapping,
- ingestion batch skeleton,
- checkpoint skeleton.

Recommended logical entity split:

- `TenantWarehouseMapping`
- `IngestionBatch`
- `IngestionCheckpoint`

The exact names may differ, but the concepts must be clearly represented.

### 2. CLI command in `backend/Kds.Ai.Cli`

Create an administrative command equivalent to `register-tenant` that:

- accepts `tenant_id`,
- accepts `tenant_database`,
- upserts the tenant warehouse mapping in `kdsaidb`,
- initializes lightweight control-plane metadata such as active state and timestamps.

Registration safety rule:

- if `tenant_id` does not exist, create the mapping,
- if `tenant_id` exists with the same `tenant_database`, allow idempotent confirmation/update of lightweight metadata,
- if `tenant_id` exists with a different `tenant_database`, fail clearly instead of silently changing the warehouse target.

## Files to Modify

### 3. `backend/Kds.Ai.Data/KdsAiDbContext.cs`

Register the new metadata sets in the application database context.

## Required Model Shape

### Tenant warehouse mapping

Minimum logical fields:

- `tenant_id`
- `tenant_database`
- `is_active`
- `created_at`
- `updated_at`

For phase 1, this mapping is the lightweight control-plane state for tenant warehouse registration.

Registration rule:

- newly registered tenants should start with `is_active = false`,
- `is_active` should only become `true` after successful bootstrap.

### Ingestion batch skeleton

Minimum logical fields:

- `batch_id`
- `tenant_id`
- `tenant_database`
- `ingestion_mode`
- `source_type`
- `status`
- `received_at`
- `load_started_at`
- `load_completed_at`
- `raw_s3_path` nullable
- `load_s3_path` nullable

### Checkpoint skeleton

Minimum logical fields:

- `tenant_id`
- `source_type`
- `checkpoint_key`
- `checkpoint_value`
- `updated_at`
- `last_successful_batch_id` nullable

## Acceptance Criteria

- [x] Metadata entities are created in `Kds.Ai.Data`
- [x] EF configurations follow project conventions
- [x] DbSets are registered in `KdsAiDbContext`
- [x] A migration is created for the new metadata tables
- [x] `tenant_id -> tenant_database` can be persisted in `kdsaidb`
- [x] Tenant registration persists `is_active`, `created_at`, and `updated_at`
- [x] Batch skeleton metadata can be persisted in `kdsaidb`
- [x] Checkpoint skeleton metadata can be persisted in `kdsaidb`
- [x] A CLI command exists to register or update tenant warehouse mapping metadata
- [x] Tenant registration does not silently change `tenant_database` for an existing tenant
- [x] New tenant registration initializes `is_active = false`
- [x] Re-running tenant registration for the same `tenant_id` and `tenant_database` is idempotent
- [x] Solution builds without errors

## Notes

- Keep the metadata intentionally small and extensible.
- Do not over-model full ETL runtime concerns yet.
- This task creates the authoritative metadata store for later tenant routing.
- Tenant registration should be modeled as a separate administrative operation from physical bootstrap.
- The registration command should behave like a lightweight control-plane entry point, not just a raw mapping writer.
- Repointing a tenant to a different warehouse database should require a separate later operation, not normal registration flow.
- Registration should not imply readiness for warehouse use; bootstrap success is the activation boundary.