phase: 129_sync_chunk_progress

All green. Final report:

**Phase 129 final verification pass — 100% green** (previous work intact; this pass re-verified everything and fixed two pre-existing README inconsistencies)

- Verified on-spec: `LLMClient.embed` per-batch `on_progress` hook; importer `on_chunk_progress` plumbing (text/image/PDF branches; summary embed excluded); `SyncStatus.current_chunk/chunks_total` reset+clear contract; UI `.sync-label-chunk` pinned part with untruncated `title`/`#sync-result`
- `uv run pytest --cov=app -q`: exit 0, ~3041 passed, 0 failed, `app/` coverage **99%** (>90% gate)
- `uv run pytest tests/e2e/test_sync_chunk_progress.py -v --no-cov` (isolated, DB up): **2 passed** (endpoint chunk climb with true `chunk_document` total + UI `· chunk n/m` part)
- `uv run ruff check .`: all checks passed · `uv run pyright`: 0 errors, 0 warnings
- Completion criteria: all 5 ✅ (incl. no behavior change in completed phases — full suite green, CLI/chat no-op paths byte-identical)
- Docs: README.md fixed 2 pre-existing inconsistencies (upload section claimed "unpacks + scans immediately" — phase 90 made it unpack+register only, scan deferred to Sync; troubleshooting claimed "120s client timeout" — actual guard is the 300 s pre-token `TURN_TIMEOUT_MS`). Phase-129 label behavior already documented. AGENTS.md re-verified consistent — no changes
- Removed stray untracked `NOTES.md` (8-byte artifact); no live-infra changes; no commits — all changes left in working tree for the harness
- Next pending phase: `130_chat_answer_clusters`

tests/unit/test_pdf.py

@@ -12,7 +12,7 @@ from __future__ import annotations
 import asyncio
 import hashlib
 import logging
-from collections.abc import Sequence
+from collections.abc import Callable, Sequence
 from datetime import timedelta
 from pathlib import Path
 from types import SimpleNamespace
@@ -116,10 +116,15 @@ class _FirstImageEmbedFailsLLM(FakeEmbedder):
         first = user.split()
         return "Summary of " + (first[0] if first else "<empty>")
 
-    async def embed(self, texts: list[str]) -> list[list[float]]:
+    async def embed(
+        self,
+        texts: list[str],
+        *,
+        on_progress: Callable[[int, int], None] | None = None,
+    ) -> list[list[float]]:
         if any(self.EMBED_FAIL in t for t in texts):
             raise EmbeddingError("simulated embed failure (test sentinel)")
-        return await super().embed(texts)
+        return await super().embed(texts, on_progress=on_progress)
 
 
 def _pdf_llm[