partly or unimplemented features - now implemented

docs/modules/mirror/architecture.md

@@ -58,3 +58,50 @@ The `StellaOpsMirror` connector in Concelier handles:
 * Concelier: `../concelier/architecture.md`
 * AirGap: `../airgap/architecture.md`
 * Provenance observers: `./provenance/observers.md`
+
+---
+
+## 3) Mirror Creator Core (2026-02-08)
+
+Sprint `SPRINT_20260208_041_Mirror_mirror_creator` adds a deterministic core library at:
+
+- `src/Mirror/StellaOps.Mirror.Creator/StellaOps.Mirror.Creator.Core.csproj`
+
+### Implemented Contracts
+
+- `IMirrorCreatorService`
+  - `UpsertSourceAsync(MirrorSourceConfiguration source, CancellationToken cancellationToken = default)`
+  - `GetSourcesAsync(string tenantId, CancellationToken cancellationToken = default)`
+  - `CreateSyncPlanAsync(MirrorSyncRequest request, CancellationToken cancellationToken = default)`
+  - `RecordSyncResultAsync(MirrorSyncResult result, CancellationToken cancellationToken = default)`
+- Model types in `MirrorModels.cs`:
+  - `MirrorSourceConfiguration`
+  - `MirrorSyncRequest`
+  - `MirrorSyncPlan` and `MirrorSyncPlanItem`
+  - `MirrorSyncResult`
+  - `MirrorContentKind` and `MirrorSyncMode`
+- Options in `MirrorCreatorOptions` with configurable `OutputRoot`.
+- DI registration in `MirrorServiceCollectionExtensions.AddMirrorCreator(...)`.
+
+### Determinism Guarantees
+
+- Tenant and source IDs are normalized to lowercase-trimmed values.
+- Source ordering is stable (ordinal sort by source ID per tenant).
+- Plan IDs are generated from canonical plan content using SHA-256.
+- Output bundle path format is stable:
+  - `<outputRoot>/<tenant>/<source>/<yyyyMMddHHmmss>.bundle.json`
+- Sync mode behavior:
+  - `Full` when no prior cursor exists.
+  - `Incremental` after successful cursor recording via `RecordSyncResultAsync`.
+
+### Test Evidence
+
+- Test project: `src/Mirror/__Tests/StellaOps.Mirror.Creator.Core.Tests/`
+- Executed: `dotnet test src/Mirror/__Tests/StellaOps.Mirror.Creator.Core.Tests/StellaOps.Mirror.Creator.Core.Tests.csproj`
+- Result on 2026-02-08: Passed `4/4` tests.
+
+### Current Boundaries
+
+- Implementation is currently in-memory and does not persist checkpoints to a backing store.
+- No dedicated HTTP endpoints or CLI command group are added in this sprint.
+- Runtime mirror transport/execution remains the responsibility of future integration work.