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

docs/architecture/01-state-and-stores.md

@@ -398,7 +398,7 @@ every keystroke. A startup subscriber observes the draft and debounces the expen
 work:
 
 ```ts
-// src/app/orchestration/persistence.ts
+// src/app/orchestration/snippet-persistence.ts
 import { useSnippetStore } from '../stores/SnippetStore';
 import { saveSnippet } from '../infrastructure/snippet-store'; // IndexedDB adapter
 

docs/architecture/02-persistence.md

@@ -451,7 +451,7 @@ export async function saveSnippet(s: Snippet): Promise<void> {
 fire-and-forget `void saveSnippet(n)` re-buries the very error the adapter took care to
 throw. Persistence write-backs are wired as store subscribers, so the surfacing path is:
 
-`orchestration/persistence.ts` (write-through `.catch`) / `orchestration/startup.ts` (load
+`orchestration/snippet-persistence.ts` (write-through `.catch`) / `orchestration/startup.ts` (load
 `.catch`, then run in memory) → `services/storage-errors.ts` (pure error→message mapper) →
 `notify()` (`stores/NotificationStore`) → `Toaster`.
 

docs/architecture/07-naming-and-relationships.md

@@ -260,22 +260,14 @@ export function datasetUsageCounts(
 ): Map<string, number>;
 ```
 
-```ts
-// src/app/services/RelationshipService.ts — snapshot wrapper for non-reactive callers
-
-import { snippetsReferencingDataset } from '../../core/relationships';
-import { useSnippetStore } from '../stores/SnippetStore';
-
-export function findSnippetsReferencingDataset(name: string): Snippet[] {
-  return snippetsReferencingDataset(useSnippetStore.getState().snippets, name);
-}
-```
-
-The reactive UI does **not** go through the service: a component subscribed to
-`snippets` calls the core helper directly, so the badge and Linked Snippets list
-update the moment any snippet's draft changes its refs (auto-save) or it is
-published — no duplicated matching logic, no `getState()` snapshot that would
-miss updates.
+There is no app-layer wrapper module around the scan. The reactive UI — a
+component subscribed to `snippets` — calls the core helper directly, so the
+badge and Linked Snippets list update the moment any snippet's draft changes
+its refs (auto-save) or it is published. A non-reactive caller binds the same
+helper to a snapshot inline at its call site
+(`snippetsReferencingDataset(useSnippetStore.getState().snippets, name)`) —
+one matching implementation, no `getState()` wrapper that would go stale in
+reactive code.
 
 **Do**
 
@@ -283,7 +275,7 @@ miss updates.
   reactive and snapshot callers share it. It is O(snippets) but the collections
   are small (library budget ~5 MB); clarity beats an index.
 - Call the core helper directly from a store-subscribed component for reactivity;
-  use the service wrapper only from non-reactive (snapshot) code.
+  bind it to a `getState()` snapshot inline for non-reactive code.
 
 **Don't**
 
@@ -334,9 +326,10 @@ export function dedupeIncomingDatasetNames(
 ```
 
 > If imported snippets reference the renamed dataset, their `datasetRefs` and
-> specs must be rewritten to the new name too — reuse the rename machinery in
-> §6 over the imported snippet set, or run `renameDatasetEverywhere` per applied
-> rename after the import is committed.
+> specs must be rewritten to the new name too. The import flow does this purely,
+> before anything is committed: `applyDatasetRenamesToSnippets`
+> (`core/import-normalize`) rewrites the incoming snippet set per applied rename
+> using the same `renameDatasetInSpec` machinery as §6.
 
 ### 5.1 Where the import/export flow lives, and its rules
 
@@ -427,43 +420,22 @@ export function renameDatasetInSpec(spec: Json, oldName: string, newName: string
 }
 ```
 
-```ts
-// src/app/services/RelationshipService.ts — thin store coordinator
-
-import { useDatasetStore } from '../stores/DatasetStore';
-import { useSnippetStore } from '../stores/SnippetStore';
-
-/**
- * Renames a dataset and propagates the rename to every referencing snippet
- * (spec, draftSpec, and datasetRefs). Returns the number of snippets changed.
- * Caller is responsible for collision policy on `newName` (reject vs suffix).
- */
-export function renameDatasetEverywhere(
-  oldName: string,
-  newName: string,
-  now?: Date,
-): { updated: number } {
-  if (oldName === newName) return { updated: 0 };
-
-  // 1. Rename the dataset record itself.
-  const dataset = useDatasetStore.getState().datasets.find((d) => d.name === oldName);
-  if (dataset) useDatasetStore.getState().update(dataset.id, { name: newName }, now);
-
-  // 2 + 3. Delegate the spec/draftSpec/refs rewrite to the ONE rename impl — the
-  // store action that owns the snippet collection. It matches by spec+draft
-  // *content* (not `datasetRefs`, which mirrors only the draft) and recomputes
-  // `datasetRefs` from the rewritten draft. Keeping the loop in the store means
-  // the reactive editor buffer is refreshed in the same atomic update when the
-  // active snippet's draft is rewritten.
-  return { updated: useSnippetStore.getState().renameDatasetRefs(oldName, newName, now) };
-}
-```
+The one rename implementation in the live app is the store action
+**`SnippetStore.renameDatasetRefs(oldName, newName, now)`** — the action that
+owns the snippet collection. It matches by spec+draft _content_ (not
+`datasetRefs`, which mirrors only the draft), rewrites `spec`/`draftSpec` via
+`renameDatasetInSpec`, recomputes `datasetRefs` from the rewritten draft, and
+returns the number of snippets changed. Keeping the loop in the store means the
+reactive editor buffer is refreshed in the same atomic update when the active
+snippet's draft is rewritten. `DatasetStore.update` calls it whenever a save
+changes a dataset's name, so a rename propagates everywhere as part of the one
+user action — there is no separate coordinator module to call.
 
 > **Collision on rename.** The UI rename form rejects a name already in use via
 > `isNameTaken(newName, datasets, dataset.id)`. Programmatic renames (e.g. an
-> import flow) instead resolve with `makeUniqueName` before calling
-> `renameDatasetEverywhere`. The propagation function itself does not invent a
-> name — it assumes `newName` is the agreed target.
+> import flow) instead resolve with `makeUniqueName` first. The propagation
+> action itself does not invent a name — it assumes `newName` is the agreed
+> target.
 
 **Do**
 
@@ -492,18 +464,17 @@ export function renameDatasetEverywhere(
 
 ## 7. Where things live
 
-| Concern                                                                  | Location                                  | Pure?               | Tested      |
-| ------------------------------------------------------------------------ | ----------------------------------------- | ------------------- | ----------- |
-| `makeUniqueName`, `isNameTaken`                                          | `src/core/naming.ts`                      | yes                 | unit        |
-| `extractDatasetRefs`, `recomputeDatasetRefs`                             | `src/core/spec-refs.ts`                   | yes                 | unit        |
-| `renameDatasetInSpec`                                                    | `src/core/spec-refs.ts`                   | yes                 | unit        |
-| `snippetsReferencingDataset`, `datasetUsageCounts` (reverse-lookup scan) | `src/core/relationships.ts`               | yes                 | unit        |
-| `findSnippetsReferencingDataset`, usage count (snapshot wrappers)        | `src/app/services/RelationshipService.ts` | no (reads store)    | integration |
-| `renameDatasetEverywhere` → `{ updated }`                                | `src/app/services/RelationshipService.ts` | no (mutates stores) | integration |
-| `dedupeIncomingDatasetNames`                                             | `src/core/import-normalize.ts`            | yes                 | unit        |
+| Concern                                                                  | Location                         | Pure?               | Tested      |
+| ------------------------------------------------------------------------ | -------------------------------- | ------------------- | ----------- |
+| `makeUniqueName`, `isNameTaken`                                          | `src/core/naming.ts`             | yes                 | unit        |
+| `extractDatasetRefs`, `recomputeDatasetRefs`                             | `src/core/spec-refs.ts`          | yes                 | unit        |
+| `renameDatasetInSpec`                                                    | `src/core/spec-refs.ts`          | yes                 | unit        |
+| `snippetsReferencingDataset`, `datasetUsageCounts` (reverse-lookup scan) | `src/core/relationships.ts`      | yes                 | unit        |
+| `renameDatasetRefs` → updated count (rename propagation)                 | `src/app/stores/SnippetStore.ts` | no (mutates stores) | integration |
+| `dedupeIncomingDatasetNames`                                             | `src/core/import-normalize.ts`   | yes                 | unit        |
 
 The dividing line: anything that takes plain data and returns plain data is
 **core** and unit-tested in isolation; anything that reaches into a Zustand store
-is an **app service**. The rule of thumb — _the **draft** spec is the source of
+is a **store action or app service**. The rule of thumb — _the **draft** spec is the source of
 truth, `datasetRefs` mirrors it, the reverse lookup is derived_ — is what keeps
 the bidirectional link from ever needing manual repair.

docs/architecture/10-interaction-and-feedback.md

@@ -138,7 +138,7 @@ control and freedom," #5 "error prevention"; spec §10 Reliability).
 
 - **No silent data loss.** Edits auto-save as a **draft**; a known-good **published**
   version is always preserved separately (§03D). A failed persist **surfaces as a toast**,
-  never a swallowed promise (`orchestration/persistence.ts`).
+  never a swallowed promise (`orchestration/snippet-persistence.ts`).
 - **A marked exit from every committed change.** Revert restores the published spec;
   Escape closes modals; delete/revert/reset require confirmation first.
 - **Resilient rendering recovers on its own.** An invalid spec shows a readable error and

src/app/orchestration/snippet-persistence.test.ts

@@ -19,7 +19,7 @@ vi.mock('../infrastructure/snippet-store', async (importOriginal) => {
 import { saveSnippet, deleteSnippet, StorageQuotaError } from '../infrastructure/snippet-store';
 import { useNotificationStore } from '../stores/NotificationStore';
 import { useSnippetStore } from '../stores/SnippetStore';
-import { AUTOSAVE_DEBOUNCE_MS, wirePersistence } from './persistence';
+import { AUTOSAVE_DEBOUNCE_MS, wireSnippetPersistence } from './snippet-persistence';
 
 const save = vi.mocked(saveSnippet);
 const del = vi.mocked(deleteSnippet);
@@ -51,7 +51,7 @@ afterEach(() => {
 describe('wireDraftAutoSave', () => {
   it('persists a settled, valid edit after the debounce', async () => {
     useSnippetStore.getState().hydrate([snippetWith('a', '{"a":1}')]);
-    teardown = wirePersistence();
+    teardown = wireSnippetPersistence();
     save.mockClear();
 
     useSnippetStore.getState().updateDraft('{"a":2}');
@@ -65,7 +65,7 @@ describe('wireDraftAutoSave', () => {
 
   it('does not persist a half-typed, unparseable buffer', async () => {
     useSnippetStore.getState().hydrate([snippetWith('a', '{"a":1}')]);
-    teardown = wirePersistence();
+    teardown = wireSnippetPersistence();
     save.mockClear();
 
     useSnippetStore.getState().updateDraft('{ "a":');
@@ -78,7 +78,7 @@ describe('wireDraftAutoSave', () => {
 describe('wireWriteThrough', () => {
   it('persists a newly created snippet', () => {
     useSnippetStore.getState().hydrate([]);
-    teardown = wirePersistence();
+    teardown = wireSnippetPersistence();
     save.mockClear();
 
     useSnippetStore.getState().createSnippet({ id: 'n', spec: '{}' });
@@ -90,7 +90,7 @@ describe('wireWriteThrough', () => {
 
   it('deletes a removed snippet without re-saving the survivors', () => {
     useSnippetStore.getState().hydrate([snippetWith('a', '{}'), snippetWith('b', '{}')]);
-    teardown = wirePersistence();
+    teardown = wireSnippetPersistence();
     save.mockClear();
 
     useSnippetStore.getState().removeSnippet('a');
@@ -103,7 +103,7 @@ describe('wireWriteThrough', () => {
 
   it('ignores state changes that do not touch the snippets array', () => {
     useSnippetStore.getState().hydrate([snippetWith('a', '{}')]);
-    teardown = wirePersistence();
+    teardown = wireSnippetPersistence();
     save.mockClear();
 
     useSnippetStore.getState().setEditorView('published');
@@ -114,7 +114,7 @@ describe('wireWriteThrough', () => {
 
   it('surfaces a failed save as an error notification instead of losing it silently', async () => {
     useSnippetStore.getState().hydrate([]);
-    teardown = wirePersistence();
+    teardown = wireSnippetPersistence();
     save.mockClear();
     save.mockRejectedValueOnce(new StorageQuotaError());
 

src/app/orchestration/snippet-persistence.ts

@@ -1,5 +1,5 @@
 /**
- * Persistence & auto-save wiring (docs/architecture/01 §5).
+ * Snippet persistence & auto-save wiring (docs/architecture/01 §5).
  *
  * Bridges the pure SnippetStore to the IndexedDB adapter via startup
  * subscribers — the store stays browser-free, and all reads/writes funnel
@@ -61,7 +61,7 @@ function wireWriteThrough(): Unsubscribe {
 }
 
 /** Wire all persistence subscribers. Returns a teardown that detaches them. */
-export function wirePersistence(): Unsubscribe {
+export function wireSnippetPersistence(): Unsubscribe {
   const unsubs = [wireDraftAutoSave(), wireWriteThrough()];
   return () => unsubs.forEach((u) => u());
 }

src/app/orchestration/startup.ts

@@ -19,7 +19,7 @@ import { notify } from '../stores/NotificationStore';
 import { useSnippetStore } from '../stores/SnippetStore';
 import { useDatasetStore } from '../stores/DatasetStore';
 import { useCustomThemeStore } from '../stores/CustomThemeStore';
-import { wirePersistence } from './persistence';
+import { wireSnippetPersistence } from './snippet-persistence';
 import { wireDatasetPersistence } from './dataset-persistence';
 import { wireThemePersistence } from './theme-persistence';
 import { startRouting } from '../modals/UrlStateSync';
@@ -67,7 +67,7 @@ export async function initApp(): Promise<void> {
 
   // Wire persistence AFTER hydrate so write-through's baseline is the loaded set
   // — otherwise it would redundantly re-save every record on each startup.
-  wirePersistence();
+  wireSnippetPersistence();
   wireDatasetPersistence();
   wireThemePersistence();
 

src/app/services/RelationshipService.test.ts

@@ -1,72 +0,0 @@
-import { beforeEach, describe, expect, test } from 'vitest';
-import { createDataset } from '@core/dataset';
-import { createSnippet } from '@core/snippet';
-import { useDatasetStore } from '../stores/DatasetStore';
-import { useSnippetStore } from '../stores/SnippetStore';
-import {
-  datasetUsageCount,
-  findSnippetsReferencingDataset,
-  renameDatasetEverywhere,
-} from './RelationshipService';
-
-const T = new Date('2026-06-01T00:00:00Z');
-
-/** Seed a snippet whose published spec references `datasetName`. */
-function seedSnippet(id: string, datasetName: string) {
-  return createSnippet({
-    id,
-    spec: JSON.stringify({ data: { name: datasetName }, mark: 'bar' }),
-    now: T,
-  });
-}
-
-beforeEach(() => {
-  useDatasetStore.getState().reset();
-  useSnippetStore.getState().reset();
-});
-
-describe('reverse lookup', () => {
-  test('finds referencing snippets case-insensitively and counts them', () => {
-    useSnippetStore.getState().hydrate([seedSnippet('a', 'Sales'), seedSnippet('b', 'SALES')], 'a');
-    // datasetRefs are recomputed on publish; publish each active snippet to seed.
-    useSnippetStore.getState().publish(T);
-    useSnippetStore.getState().selectSnippet('b');
-    useSnippetStore.getState().publish(T);
-
-    expect(
-      findSnippetsReferencingDataset('sales')
-        .map((s) => s.id)
-        .sort(),
-    ).toEqual(['a', 'b']);
-    expect(datasetUsageCount('Sales')).toBe(2);
-    expect(datasetUsageCount('Other')).toBe(0);
-  });
-});
-
-describe('renameDatasetEverywhere', () => {
-  test('renames the dataset record and every referencing snippet', () => {
-    useDatasetStore.getState().add(
-      createDataset({
-        name: 'Sales',
-        data: [{ a: 1 }],
-        format: 'json',
-        source: 'inline',
-        now: T,
-      }),
-    );
-    useSnippetStore.getState().hydrate([seedSnippet('a', 'Sales')], 'a');
-    useSnippetStore.getState().publish(T);
-
-    const result = renameDatasetEverywhere('Sales', 'Revenue', new Date('2026-07-01T00:00:00Z'));
-
-    expect(result).toEqual({ updated: 1 });
-    expect(useDatasetStore.getState().datasets[0].name).toBe('Revenue');
-    const s = useSnippetStore.getState().snippets[0];
-    expect(s.datasetRefs).toEqual(['Revenue']);
-    expect(s.spec).toContain('"Revenue"');
-  });
-
-  test('is a no-op when old and new names are equal', () => {
-    expect(renameDatasetEverywhere('Sales', 'Sales')).toEqual({ updated: 0 });
-  });
-});

src/app/services/RelationshipService.ts

@@ -1,54 +0,0 @@
-/**
- * Snippet ↔ dataset relationships (docs/architecture/07 §4 + §6).
- *
- * The bidirectional link is name-based and has a single source of truth: a
- * snippet's `datasetRefs` (recomputed from its draft spec — the version being
- * edited — on every draft change and on publish). The reverse direction —
- * "which snippets use this dataset" — is therefore DERIVED by a scan,
- * never stored, so it can't drift. Rename is the one graph operation: it renames
- * the dataset record and propagates the new name into every referencing snippet's
- * spec/draftSpec/refs.
- *
- * These functions read and mutate Zustand stores, so they live in the app layer
- * (the pure rewrite/extraction helpers they build on live in `core/spec-refs`).
- */
-
-import type { Snippet } from '@core/snippet';
-import { snippetsReferencingDataset } from '@core/relationships';
-import { useDatasetStore } from '../stores/DatasetStore';
-import { useSnippetStore } from '../stores/SnippetStore';
-
-// The reverse-lookup scan itself is the pure `snippetsReferencingDataset`
-// (`core/relationships`) — the *one* implementation arch/07 §6 calls for. These
-// wrappers just bind it to a store snapshot for non-reactive callers (e.g. a
-// programmatic rename); the reactive UI calls the core helper directly with its
-// live `snippets` selection, so neither side duplicates the matching logic.
-
-/** Snippets whose `datasetRefs` include `name` (case-insensitive), from the store. */
-export function findSnippetsReferencingDataset(name: string): Snippet[] {
-  return snippetsReferencingDataset(useSnippetStore.getState().snippets, name);
-}
-
-/** Count for the dataset usage badge (spec §05 → List item). */
-export function datasetUsageCount(name: string): number {
-  return findSnippetsReferencingDataset(name).length;
-}
-
-/**
- * Rename a dataset and propagate everywhere (docs/architecture/07 §6): renames
- * the dataset record, then rewrites every referencing snippet's spec, draftSpec,
- * and datasetRefs (via `SnippetStore.renameDatasetRefs`, the single rename impl).
- * The caller is responsible for collision policy on `newName` (the edit form
- * rejects a taken name; programmatic paths pre-resolve a unique one). Returns the
- * number of snippets updated, as `{ updated }` (arch/07 §6).
- */
-export function renameDatasetEverywhere(
-  oldName: string,
-  newName: string,
-  now?: Date,
-): { updated: number } {
-  if (oldName === newName) return { updated: 0 };
-  const dataset = useDatasetStore.getState().datasets.find((d) => d.name === oldName);
-  if (dataset) useDatasetStore.getState().update(dataset.id, { name: newName }, now);
-  return { updated: useSnippetStore.getState().renameDatasetRefs(oldName, newName, now) };
-}

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();

src/app/stores/SnippetStore.ts

@@ -5,9 +5,9 @@
  * active, and the live editor buffer (`draftText`). Actions are the single place
  * snippet state mutates, so they are unit-testable without a DOM or IndexedDB.
  *
- * Persistence is NOT done here — a startup subscriber (orchestration/persistence)
- * observes this store and writes through to the IndexedDB adapter. That keeps the
- * store pure and free of browser APIs.
+ * Persistence is NOT done here — a startup subscriber
+ * (orchestration/snippet-persistence) observes this store and writes through to
+ * the IndexedDB adapter. That keeps the store pure and free of browser APIs.
  *
  * Draft/published model (spec §03D): every snippet carries a published `spec`
  * and a working `draftSpec`. Ordinary editing — keystrokes, auto-save — touches

src/core/relationships.ts

@@ -6,8 +6,8 @@
  * scan, never stored, so it can't drift. This module is that scan's single pure
  * implementation: it takes plain snippet records and a name and returns plain
  * data, so the same logic serves both the reactive UI (the Dataset Manager passes
- * its live `snippets` selection) and the non-reactive `RelationshipService` (which
- * passes a store snapshot). One definition, per arch/07 §6 ("'who references this'
+ * its live `snippets` selection) and any non-reactive caller (which passes a
+ * store snapshot inline). One definition, per arch/07 §6 ("'who references this'
  * has exactly one implementation").
  *
  * Matching is **case-insensitive**, mirroring the naming policy (`core/naming`):