fix(git-sync): subpages round-trips (was {{SUBPAGES}} literal) + exhaustive all-node round-trip test

subpages exported to the literal `{{SUBPAGES}}`, which has no markdown/HTML
inverse, so on re-import it came back as a plain paragraph holding the visible
text "{{SUBPAGES}}" — the embed rendered as that literal string on the page
after a sync (round-trip data loss, seen live). It now emits the schema-matching
`<div data-type="subpages">` like every other embed node, so the schema's
parseHTML rebuilds the subpages node. Also dropped the leaf-atom content-hole
in the subpages renderHTML.

New committed regression coverage:
- packages/git-sync/test/roundtrip-all-nodes.test.ts — exhaustive serialize ->
  deserialize round trip for ALL 40 node/mark types; each asserts the node/mark
  survives and no `{{...}}` literal leaks. This is the test that caught subpages.
- §13.1 gate (git-sync-converter-gate.spec.ts): subpages added to the green
  corpus (round-trips through the REAL server schema).
- Corrected two PR-authored tests that asserted the old {{SUBPAGES}} loss as
  "by design" — they now assert the fixed round trip.

Also folds in review #1679 coverage-gap tests (no prod change): orchestrator
pollTick/enabledSpaces, datasource 3-way merge dispatch, page.repo
last_updated_source provenance SQL.

git-sync vitest 659 (+1 expected-fail), server tsc clean, server specs green.

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

apps/server/src/collaboration/git-sync-converter-gate.spec.ts

@@ -360,6 +360,15 @@ const CORPUS: Record<string, any> = {
       content: [para(text('quote at the end'))],
     },
   ),
+
+  // Atom embeds that carry no inline text: they must round-trip via their
+  // schema-matching HTML (data-type div), NOT a literal that re-imports as plain
+  // text. `subpages` used to export as the literal "{{SUBPAGES}}" and came back
+  // as visible text on the page (red-team round-trip data loss) — this locks it.
+  // editor-ext materializes the `recursive: false` default on import, so the
+  // fixture pre-authors it to sit at the round-trip fixpoint (matches the other
+  // default-materializing fixtures above).
+  'subpages embed': doc({ type: 'subpages', attrs: { recursive: false } }),
 };
 
 describe('git-sync converter §13.1 idempotency gate (editor-ext schema)', () => {

apps/server/src/database/repos/page/page.repo.spec.ts

@@ -0,0 +1,157 @@
+import {
+  Kysely,
+  CamelCasePlugin,
+  DummyDriver,
+  PostgresAdapter,
+  PostgresIntrospector,
+  PostgresQueryCompiler,
+  CompiledQuery,
+} from 'kysely';
+import { PageRepo } from './page.repo';
+import type { KyselyDB } from '../../types/kysely.types';
+
+/**
+ * SQL-builder unit test for the git-sync provenance stamp on PageRepo's
+ * soft-delete / restore paths (PR #119 review). Both `removePage` and
+ * `restorePage` take an optional `lastUpdatedSource` arg and conditionally fold
+ * it into the recursive-subtree `UPDATE pages SET ...` via
+ * `...(lastUpdatedSource ? { lastUpdatedSource } : {})`. The change-listener
+ * loop-guard reads `last_updated_source = 'git-sync'` to recognize git-sync's own
+ * writes and skip the echo cycle; this test guards that the stamp is present when
+ * the arg is supplied and ABSENT when it is omitted (an ordinary user delete must
+ * not clobber the column).
+ *
+ * Harness: the same compile-only Kysely/DummyDriver pattern as
+ * space.repo.spec.ts, plus the production `CamelCasePlugin` (so the compiled SQL
+ * carries the real snake_case column names, e.g. `last_updated_source`) and a
+ * thin driver that returns ONE fixed row for every query. The fixed row is what
+ * lets the repo's guard reads (root snapshot / recursive descendants / restore
+ * target) resolve non-empty so execution reaches the subtree UPDATE we assert on
+ * — a bare DummyDriver returns no rows and both methods short-circuit before the
+ * update. We never hit a real database; we capture each compiled statement via
+ * Kysely's `log` hook and inspect the `update "pages" set ...` SQL.
+ */
+describe('PageRepo — git-sync provenance on soft-delete / restore SQL', () => {
+  // A single row shaped to satisfy every column the repo reads off its guard
+  // queries. `parentPageId: null` keeps restorePage on the simple path (no
+  // parent-detach UPDATE), so the only `update "pages"` statement is the one we
+  // assert on.
+  const FIXED_ROW = {
+    id: 'p1',
+    slugId: 's1',
+    title: 'Doc',
+    icon: null,
+    position: 'a0',
+    spaceId: 'space-1',
+    parentPageId: null,
+    deletedAt: null,
+  };
+
+  class FixedRowDriver extends DummyDriver {
+    async acquireConnection(): Promise<any> {
+      return {
+        async executeQuery() {
+          return { rows: [{ ...FIXED_ROW }] };
+        },
+        // eslint-disable-next-line @typescript-eslint/no-empty-function
+        async *streamQuery() {},
+      };
+    }
+  }
+
+  interface Captured {
+    sql: string;
+    parameters: readonly unknown[];
+  }
+
+  // Compile-only Kysely on the Postgres dialect (CamelCasePlugin for real column
+  // names) whose `log` hook records every executed statement's compiled SQL.
+  function makeRepoCapturingSql() {
+    const captured: Captured[] = [];
+    const db = new Kysely<any>({
+      dialect: {
+        createAdapter: () => new PostgresAdapter(),
+        createDriver: () => new FixedRowDriver(),
+        createIntrospector: (d) => new PostgresIntrospector(d),
+        createQueryCompiler: () => new PostgresQueryCompiler(),
+      },
+      plugins: [new CamelCasePlugin()],
+      log: (event) => {
+        if (event.level === 'query') {
+          const q = event.query as CompiledQuery;
+          captured.push({ sql: q.sql, parameters: q.parameters });
+        }
+      },
+    });
+
+    const repo = new PageRepo(
+      db as unknown as KyselyDB,
+      {} as any,
+      { emit: jest.fn() } as any,
+    );
+    // Find the single subtree UPDATE on pages (collapse whitespace for matching).
+    const getUpdatePagesSql = (): Captured | undefined =>
+      captured
+        .map((c) => ({ ...c, sql: c.sql.replace(/\s+/g, ' ') }))
+        .find((c) => /update "pages" set/i.test(c.sql));
+    return { repo, getUpdatePagesSql };
+  }
+
+  describe('removePage', () => {
+    it("stamps last_updated_source = 'git-sync' on the subtree soft-delete when the provenance arg is supplied", async () => {
+      const { repo, getUpdatePagesSql } = makeRepoCapturingSql();
+
+      await repo.removePage('p1', 'user-1', 'ws-1', 'git-sync');
+
+      const update = getUpdatePagesSql();
+      expect(update).toBeDefined();
+      // The provenance column is in the UPDATE's SET clause...
+      expect(update!.sql).toContain('"last_updated_source" =');
+      // ...with the 'git-sync' marker as the bound value.
+      expect(update!.parameters).toContain('git-sync');
+      // Sanity: it is still the soft-delete UPDATE (sets deleted_at too).
+      expect(update!.sql).toContain('"deleted_at" =');
+    });
+
+    it('OMITS last_updated_source from the soft-delete when the provenance arg is undefined', async () => {
+      const { repo, getUpdatePagesSql } = makeRepoCapturingSql();
+
+      await repo.removePage('p1', 'user-1', 'ws-1');
+
+      const update = getUpdatePagesSql();
+      expect(update).toBeDefined();
+      // Ordinary user delete: the column must NOT be touched (keeps prior value).
+      expect(update!.sql).not.toContain('last_updated_source');
+      expect(update!.parameters).not.toContain('git-sync');
+      // It is still the soft-delete UPDATE.
+      expect(update!.sql).toContain('"deleted_at" =');
+    });
+  });
+
+  describe('restorePage', () => {
+    it("stamps last_updated_source = 'git-sync' on the subtree restore when the provenance arg is supplied", async () => {
+      const { repo, getUpdatePagesSql } = makeRepoCapturingSql();
+
+      await repo.restorePage('p1', 'ws-1', 'git-sync');
+
+      const update = getUpdatePagesSql();
+      expect(update).toBeDefined();
+      expect(update!.sql).toContain('"last_updated_source" =');
+      expect(update!.parameters).toContain('git-sync');
+      // Sanity: it is the restore UPDATE (clears deleted_at).
+      expect(update!.sql).toContain('"deleted_at" =');
+    });
+
+    it('OMITS last_updated_source from the restore when the provenance arg is undefined', async () => {
+      const { repo, getUpdatePagesSql } = makeRepoCapturingSql();
+
+      await repo.restorePage('p1', 'ws-1');
+
+      const update = getUpdatePagesSql();
+      expect(update).toBeDefined();
+      expect(update!.sql).not.toContain('last_updated_source');
+      expect(update!.parameters).not.toContain('git-sync');
+      expect(update!.sql).toContain('"deleted_at" =');
+    });
+  });
+});

apps/server/src/integrations/git-sync/services/git-sync.orchestrator.spec.ts

@@ -19,6 +19,14 @@ jest.mock('../git-sync.loader', () => ({
 }));
 
 import { Logger } from '@nestjs/common';
+import {
+  Kysely,
+  DummyDriver,
+  PostgresAdapter,
+  PostgresIntrospector,
+  PostgresQueryCompiler,
+  CompiledQuery,
+} from 'kysely';
 import {
   GitSyncOrchestrator,
   GitSyncLockHeldError,
@@ -466,4 +474,91 @@ describe('GitSyncOrchestrator', () => {
       expect(built.scheduler.addInterval).not.toHaveBeenCalled();
     });
   });
+
+  // The poll-safety backstop: each tick enumerates the STRICT opt-in spaces and
+  // reconciles each one under its own lock. We drive the private `pollTick()`
+  // directly and (separately) compile `enabledSpaces()` to assert its opt-in SQL.
+  describe('pollTick + enabledSpaces (strict opt-in backstop)', () => {
+    it('runs runOnce exactly once per enabled space, with the right (spaceId, workspaceId)', async () => {
+      const built = build();
+      // Isolate the tick wiring from the cycle machinery: stub the enumeration
+      // and count runOnce (it never throws; here we don't exercise its body).
+      const runOnce = jest
+        .spyOn(built.orchestrator, 'runOnce')
+        .mockResolvedValue({ spaceId: 'x', ran: true });
+      jest
+        .spyOn(built.orchestrator as any, 'enabledSpaces')
+        .mockResolvedValue([
+          { spaceId: 'space-1', workspaceId: 'ws-1' },
+          { spaceId: 'space-2', workspaceId: 'ws-2' },
+        ]);
+
+      await (built.orchestrator as any).pollTick();
+
+      expect(runOnce).toHaveBeenCalledTimes(2);
+      // Per-space isolation: each space is reconciled with its OWN workspace id.
+      expect(runOnce).toHaveBeenNthCalledWith(1, 'space-1', 'ws-1');
+      expect(runOnce).toHaveBeenNthCalledWith(2, 'space-2', 'ws-2');
+    });
+
+    it('does NOT throw and runs nothing when the enabled-spaces query throws (try/catch backstop)', async () => {
+      jest.spyOn(Logger.prototype, 'error').mockImplementation(() => undefined);
+      const built = build();
+      const runOnce = jest.spyOn(built.orchestrator, 'runOnce');
+      jest
+        .spyOn(built.orchestrator as any, 'enabledSpaces')
+        .mockRejectedValue(new Error('db down'));
+
+      // A failed enumeration must never break the interval — pollTick swallows it.
+      await expect(
+        (built.orchestrator as any).pollTick(),
+      ).resolves.toBeUndefined();
+      expect(runOnce).not.toHaveBeenCalled();
+    });
+
+    it('early-returns (no enumeration, no runOnce) when git-sync is disabled', async () => {
+      const built = build({ enabled: false });
+      const enabled = jest.spyOn(built.orchestrator as any, 'enabledSpaces');
+      const runOnce = jest.spyOn(built.orchestrator, 'runOnce');
+
+      await (built.orchestrator as any).pollTick();
+
+      // Gated on the master switch before any DB work.
+      expect(enabled).not.toHaveBeenCalled();
+      expect(runOnce).not.toHaveBeenCalled();
+    });
+
+    it('compiles the STRICT opt-in enumeration SQL (spaces, deletedAt is null, enabled flag)', async () => {
+      // Inject a compile-only Kysely (DummyDriver) whose `log` hook captures the
+      // exact SQL `enabledSpaces()` runs — no fake builder, the real query is
+      // compiled. DummyDriver yields no rows; we only assert the SQL shape.
+      const built = build();
+      let captured: CompiledQuery | undefined;
+      const compileDb = new Kysely<any>({
+        dialect: {
+          createAdapter: () => new PostgresAdapter(),
+          createDriver: () => new DummyDriver(),
+          createIntrospector: (d) => new PostgresIntrospector(d),
+          createQueryCompiler: () => new PostgresQueryCompiler(),
+        },
+        log: (event) => {
+          if (event.level === 'query') captured = event.query as CompiledQuery;
+        },
+      });
+      // Swap the orchestrator's injected db for the compile-only instance.
+      (built.orchestrator as any).db = compileDb;
+
+      const rows = await (built.orchestrator as any).enabledSpaces();
+      // DummyDriver returns no rows -> empty opt-in list (the no-space default).
+      expect(rows).toEqual([]);
+
+      expect(captured).toBeDefined();
+      const sql = captured!.sql.replace(/\s+/g, ' ');
+      expect(sql).toContain('from "spaces"');
+      // deletedAt-is-null guard (live spaces only).
+      expect(sql).toContain('"deletedAt" is null');
+      // STRICT per-space opt-in: the raw jsonb flag predicate, verbatim.
+      expect(sql).toContain(`settings->'gitSync'->>'enabled' = 'true'`);
+    });
+  });
 });

apps/server/src/integrations/git-sync/services/gitmost-datasource.service.spec.ts

@@ -48,6 +48,11 @@ jest.mock('../git-sync.loader', () => ({
 
 import * as Y from 'yjs';
 import { GitmostDataSourceService } from './gitmost-datasource.service';
+// The body-write seam picks 2-way vs 3-way merge based on whether a base doc was
+// built. We spy on the real module exports (ts-jest CJS output references them
+// through the namespace object, so the spies intercept the SUT's calls) and let
+// them call through, so we assert WHICH merge ran without mocking the behaviour.
+import * as bodyMerge from './yjs-body-merge';
 
 // Focused unit/contract test for the native GitSyncClient adapter.
 // No DB, no real collab server: the repos/services/gateway are mocked and we
@@ -271,6 +276,46 @@ describe('GitmostDataSourceService', () => {
       // The body fragment is non-empty: the incoming block was merged in.
       expect(realDoc.getXmlFragment('default').length).toBeGreaterThan(0);
     });
+
+    // The 2-way path (no base) is covered above; this exercises the THREE-WAY
+    // branch that only fires when a `baseMarkdown` is supplied (review #5).
+    describe('with a baseMarkdown (three-way merge)', () => {
+      afterEach(() => jest.restoreAllMocks());
+
+      it('builds a base doc and dispatches to mergeXmlFragments3Way (not the 2-way merge)', async () => {
+        const { service, mocks } = build();
+        mocks.pageRepo.findById.mockResolvedValue({
+          id: 'p1',
+          updatedAt: new Date('2026-06-20T11:00:00.000Z'),
+        });
+        // Spy through to the real implementations so we observe the dispatch.
+        const merge3 = jest.spyOn(bodyMerge, 'mergeXmlFragments3Way');
+        const merge2 = jest.spyOn(bodyMerge, 'mergeXmlFragments');
+
+        await service
+          .bind(CTX)
+          .importPageMarkdown('p1', '# Full\n\ngit', '# Base\n\nbase');
+
+        // The body write was staged through collab as before.
+        expect(mocks.conn.transact).toHaveBeenCalledTimes(1);
+        expect(typeof mocks.conn.capturedFn).toBe('function');
+
+        // Running the captured merge against a real live doc takes the 3-way path:
+        // the base was parsed/built and the 3-way helper is invoked with three
+        // fragments; the 2-way fallback is NOT used.
+        const liveDoc = new Y.Doc();
+        expect(() => mocks.conn.capturedFn?.(liveDoc)).not.toThrow();
+
+        expect(merge3).toHaveBeenCalledTimes(1);
+        expect(merge2).not.toHaveBeenCalled();
+        const [liveFrag, gitFrag, baseFrag] = merge3.mock.calls[0];
+        expect(liveFrag).toBeInstanceOf(Y.XmlFragment);
+        expect(gitFrag).toBeInstanceOf(Y.XmlFragment);
+        // The third arg is the BASE fragment — proof the base markdown was parsed
+        // and converted into its own doc for the common-ancestor comparison.
+        expect(baseFrag).toBeInstanceOf(Y.XmlFragment);
+      });
+    });
   });
 
   describe('createPage', () => {