phase: 147_sync_changed_only

All defaults match. Verification complete — everything is green with no defects found.

**Phase 147 final verification pass — report**

- All 3 task files found in `complete/147_sync_changed_only/` → verification pass only; no code changes needed.
- Verified: migration 0025 (`documents.file_hash` nullable String(64), no index) + model field; fast path at top of `_index_file` (streamed 1 MiB sha256 → row lookup → `_unchanged_doc`); stamping on all three branches' create/update + shared helper; pre-phase NULL-hash fallthrough; retriever/`content_hash` untouched.
- **Tests:** `uv run pytest --cov=app --cov-report=term-missing` → 3438 passed, `app/` coverage **99%** (>90% ✓); `uv run pytest tests/e2e/test_sync_changed_only.py -v --no-cov` → 3 passed in isolation ✓; `uv run ruff check . && uv run pyright` → all checks passed, 0 errors ✓; prior-phase `tests/e2e/test_sync_button.py` → 3 passed (no regression) ✓.
- **Completion criteria:** all 7 pass — (1) column + round-trip ✓ (2) unchanged text/image/garbage-PDF/pictorial-PDF cost zero LLM/extraction/vision, `summary.unchanged` counted, rows byte-still ✓ (3) changed file re-indexes + re-stamps; bytes-changed/content-same stamps only ✓ (4) backfill/D1/D4 + log wordings pinned verbatim ✓ (5) `content_hash`/retriever byte-identical ✓ (6) all gates green ✓ (7) no prior-phase behavior change ✓.
- **Documentation:** full review of README.md (1,031 lines) and AGENTS.md against the code: every `.env.example`/code `BOR_*` var documented, all config defaults match `app/config.py`, quick-start/QA commands and referenced test files exist, `file://` URL + troubleshooting claims accurate; the phase's README "Updating the documents" edit is accurate. **Verified consistent — no changes needed.**
- **Notable:** no live-infrastructure changes (dev Postgres container used for the standard test gates only). Working tree left uncommitted per harness protocol.
- **Next pending phase:** `148_pdf_pages_in_sources`.

tests/integration/test_importer.py

@@ -1636,10 +1636,11 @@ def test_ikea_tar_sparse_pages_are_described_and_rerun_unchanged(
     (the owner's rationale — more information is better for the
     embeddings), the title is the metadata title, the digest is over
     the FINAL content, and a re-sync with the same fake lands
-    ``unchanged`` (digest stable, byte-stable row, NO re-embed; the
-    vision calls are re-issued before the unchanged check can skip
-    them — the documented no-cache cost, the phase-133 convention,
-    A21 endorses it)."""
+    ``unchanged`` through the phase-147 FAST PATH (the raw bytes are
+    the change signal: byte-stable row, NO re-embed, and the vision
+    calls are NOT re-issued — the pass never runs on an unchanged
+    file; the pre-phase "vision re-issued before the unchanged check"
+    no-cache cost is gone)."""
     pdf_path = ikea_pdf
     llm = _image_llm(
         tmp_path,
@@ -1724,20 +1725,19 @@ def test_ikea_tar_sparse_pages_are_described_and_rerun_unchanged(
             f"(min_chars={min_chars})"
         ]
 
-        # The re-sync with the SAME fake: ``unchanged`` — the final
-        # content is a pure function of the fixture + the canned
-        # replies, so the digest matches and the row is skipped (no
-        # re-chunk, no re-embed, no re-summary, no KB change). The
-        # vision calls ARE re-issued (the documented no-cache cost —
-        # the phase-133 convention; a non-deterministic vision model
-        # re-describes the row each sync: a cost, not a bug).
+        # The re-sync with the SAME fake: ``unchanged`` through the
+        # phase-147 fast path — the raw bytes are the change signal,
+        # so the pass never re-runs: no re-render, the vision calls
+        # are NOT re-issued (the pre-phase "vision re-issued before
+        # the unchanged check can skip them" no-cache cost is gone),
+        # no re-chunk, no re-embed, no re-summary, no KB change.
         embeds1 = len(llm.calls)
         pictorial1 = len(llm.pictorial_texts)
         content1, digest1 = doc.content, doc.content_hash
         s2 = asyncio.run(import_sources([pdf_path.parent], llm, session=db))
         assert (s2.added, s2.updated, s2.unchanged) == (0, 0, 1)
-        assert s2.pdfs_pictorial == 1  # the pass re-fired
-        assert len(llm.pictorial_texts) == 2 * pictorial1  # re-issued (cost)
+        assert s2.pdfs_pictorial == 0  # the pass did not re-fire
+        assert len(llm.pictorial_texts) == pictorial1  # NO re-issued vision
         assert len(llm.calls) == embeds1, "unchanged: no re-embed"
         assert s2.changed_paths == [], "unchanged: no KB change recorded"
         doc2 = db.scalar(