Services: delete dead RelationshipService; rename persistence to snippet-persistence

src/app/stores/DatasetStore.test.ts

@@ -52,6 +52,38 @@ describe('save — create', () => {
   });
 });
 
+describe('save — rename propagation (docs/architecture/07 §6)', () => {
+  test('renaming via the edit form rewrites every referencing snippet', () => {
+    store().startCreate();
+    store().updateForm({ name: 'Sales', input: '[{"a":1}]' });
+    expect(store().save(T)).toBe(true);
+
+    // A published snippet referencing the dataset by name.
+    useSnippetStore.getState().hydrate(
+      [
+        createSnippet({
+          id: 'a',
+          spec: JSON.stringify({ data: { name: 'Sales' }, mark: 'bar' }),
+          now: T,
+        }),
+      ],
+      'a',
+    );
+    useSnippetStore.getState().publish(T);
+    expect(useSnippetStore.getState().snippets[0].datasetRefs).toEqual(['Sales']);
+
+    store().startEdit();
+    store().updateForm({ name: 'Revenue' });
+    expect(store().save(new Date('2026-07-01T00:00:00Z'))).toBe(true);
+
+    expect(store().datasets[0].name).toBe('Revenue');
+    const s = useSnippetStore.getState().snippets[0];
+    expect(s.datasetRefs).toEqual(['Revenue']);
+    expect(s.spec).toContain('"Revenue"');
+    expect(s.spec).not.toContain('"Sales"');
+  });
+});
+
 describe('commitUrlSnapshot — create from a fetched body', () => {
   test('snapshots the body, infers format from content, and profiles it', () => {
     store().startCreate();