test(showcase): bump report-count assertion to 4 for the new chart report

seed.test.ts hardcoded 3 reports; the new showcase_hours_by_status_chart
makes it 4 (summary, chart, matrix, joined).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: os-zhuang

examples/app-showcase/test/seed.test.ts

@@ -22,9 +22,9 @@ describe('showcase stack', () => {
     expect((stack.views ?? []).length).toBeGreaterThan(0);
     expect((stack.dashboards ?? []).length).toBeGreaterThan(0);
     // ADR-0021 single-form: the former flat `tabular` TaskListReport was
-    // reclassified as a ListView (a flat list is a row lens, not analytics),
-    // leaving 3 dataset-bound analytics reports.
-    expect((stack.reports ?? []).length).toBe(3);
+    // reclassified as a ListView (a flat list is a row lens, not analytics).
+    // Four dataset-bound analytics reports: summary, chart, matrix, joined.
+    expect((stack.reports ?? []).length).toBe(4);
     expect((stack.flows ?? []).length).toBeGreaterThan(0);
     // Nine flat positions (contributor/manager/exec/auditor/ops/
     // field_ops_delegate/client_portal_user, plus finance/legal for the v16