test(domain): providing documents completes the WachtOpDocumenten wait (refs #102)

RED: the ProvideDocuments use case completes the document wait via the Workflow
Client, owner-scoped by the caller's bsn (a different bsn is NotFound), and is
best-effort when no process was started yet — mirroring WithdrawRegistration.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

services/domain/Big.Tests/ProvideDocumentsTests.cs

@@ -0,0 +1,85 @@
+using Big.Application;
+using Big.Domain;
+
+namespace Big.Tests;
+
+// S-10a (#102): the "documents received" use case. A zorgprofessional supplies the documents their
+// registration is waiting for; the handler completes the WachtOpDocumenten task via the Workflow Client
+// so the process leaves the 30-day wait and continues to beoordeling. Owner-scoped by the caller's bsn,
+// like WithdrawRegistration. (The real file upload + ZGW storage is S-10b; this is the trigger path.)
+public class ProvideDocumentsTests
+{
+    private const string Bsn = "123456782";
+
+    private static Registration Submitted(string processInstanceId = "proc-1")
+    {
+        var registration = Registration.Submit(Bsn);
+        registration.RecordProcessStarted(processInstanceId);
+        return registration;
+    }
+
+    private static ProvideDocumentsCommand Command(RegistrationId id, string bsn = Bsn) => new(id, bsn);
+
+    [Fact]
+    public async Task Providing_documents_completes_the_document_wait()
+    {
+        var store = new FakeRegistrationStore();
+        var registration = Submitted("proc-42");
+        store.Seed(registration);
+        var workflow = new FakeWorkflowClient();
+        var handler = new ProvideDocuments(store, workflow);
+
+        var outcome = await handler.HandleAsync(Command(registration.Id));
+
+        Assert.Equal(ProvideDocumentsOutcome.Accepted, outcome);
+        Assert.Equal("proc-42", workflow.CompletedDocumentWaitFor);
+    }
+
+    [Fact]
+    public async Task A_different_bsn_cannot_provide_documents()
+    {
+        // Owner-scoping: only the registration's own bsn may supply its documents. Another bsn is told
+        // NotFound (existence not revealed) and the wait is not completed.
+        var store = new FakeRegistrationStore();
+        var registration = Submitted();
+        store.Seed(registration);
+        var workflow = new FakeWorkflowClient();
+        var handler = new ProvideDocuments(store, workflow);
+
+        var outcome = await handler.HandleAsync(Command(registration.Id, bsn: "999999990"));
+
+        Assert.Equal(ProvideDocumentsOutcome.NotFound, outcome);
+        Assert.Null(workflow.CompletedDocumentWaitFor);
+    }
+
+    [Fact]
+    public async Task Providing_for_an_unknown_registration_is_not_found()
+    {
+        var store = new FakeRegistrationStore();
+        var handler = new ProvideDocuments(store, new FakeWorkflowClient());
+
+        Assert.Equal(ProvideDocumentsOutcome.NotFound, await handler.HandleAsync(Command(RegistrationId.New())));
+    }
+
+    [Fact]
+    public async Task Providing_before_a_process_started_is_accepted_without_calling_the_workflow()
+    {
+        // No process yet → no wait task to complete; the request still stands (best-effort, mirroring
+        // WithdrawRegistration) and the Workflow Client is not called.
+        var store = new FakeRegistrationStore();
+        var registration = Registration.Submit(Bsn); // no RecordProcessStarted
+        store.Seed(registration);
+        var workflow = new FakeWorkflowClient();
+        var handler = new ProvideDocuments(store, workflow);
+
+        var outcome = await handler.HandleAsync(Command(registration.Id));
+
+        Assert.Equal(ProvideDocumentsOutcome.Accepted, outcome);
+        Assert.Null(workflow.CompletedDocumentWaitFor);
+    }
+
+    [Fact]
+    public async Task Rejects_a_null_command()
+        => await Assert.ThrowsAsync<ArgumentNullException>(() =>
+            new ProvideDocuments(new FakeRegistrationStore(), new FakeWorkflowClient()).HandleAsync(null!));
+}