phase: 96_oneshot_resilience

All checks complete. Final report:

**Phase 96 (one-shot resilience) — final verification pass, all green** (all 4 task files already in `complete/`; verified the working-tree implementation against the design)

- `LLMClient.chat()` empty-content retry (D1–D3) via `_chat_once` + `_EmptyContentError` (carries `finish_reason`), under `BOR_LLM_RETRIES`/`BOR_LLM_RETRY_DELAY` — verified in diff
- `missing_folder_summaries()` + `generate_folder_summaries(only_missing=…)` — verified; `folder_summary_table_empty` deleted, both sync gates switched to the gap probe
- `.env.example` comments updated (chat-turn stream + one-shot summary calls)

**Test / lint / coverage results**
- `uv run pytest --cov=app --cov-report=term-missing` → **1988 passed**, coverage **99%** (gate >90%)
- `uv run pytest tests/e2e/test_oneshot_llm_retry.py -v --no-cov` → **2 passed** (isolated)
- Regressions, each isolated: `test_ls_tree_drilldown` 3 passed, `test_sync_button` 3 passed, `test_local_directory_sources` 3 passed, `test_llm_retry` 4 passed
- `uv run ruff check . && uv run pyright` → clean (0 errors)

**Completion criteria:** retry-then-recover unit-pinned ✓ · exhaustion + `BOR_LLM_RETRIES=0` byte-identical ✓ · streaming path untouched ✓ · gap-fill both sync paths, other rows byte-identical incl. `updated_at` ✓ · no-gap zero-burn ✓ · phase E2E green ✓ · regression E2Es green ✓ · full suite + >90% + lint/types ✓ · no completed-phase behavior change (full suite green) ✓. Commit left to the harness per executor rules (working tree, 16 files).

**Deviations:** none. **Next pending phase:** `97_kb_tree_catalog`.

tests/integration/test_sync_api.py

@@ -303,7 +303,12 @@ class FakeFolderSummaries:
     layer boundary — the real generator would read the global
     ``documents`` table and call the (real) ``LLMClient`` over the
     network. The generator only flushes, so the fake honours the
-    ``skip`` flag the same way (the zero stats, no side effects)."""
+    ``skip`` flag the same way (the zero stats, no side effects).
+    Phase 96 (task 03): the unchanged-walk gap path calls the
+    generator with ``only_missing=True`` — the fake records the flag
+    the same way it records ``skip`` (the real gap probe,
+    ``missing_folder_summaries``, runs against the real tables).
+    """
 
     ZERO = {"generated": 0, "failed": 0, "pruned": 0}
 
@@ -312,11 +317,18 @@ class FakeFolderSummaries:
         self.llms: list[LLMClient] = []
         self.sessions: list[Session] = []
         self.skip_flags: list[bool] = []
+        self.only_missing_flags: list[bool] = []
 
     async def __call__(
-        self, db: Session, llm: LLMClient, *, skip: bool = False
+        self,
+        db: Session,
+        llm: LLMClient,
+        *,
+        skip: bool = False,
+        only_missing: bool = False,
     ) -> dict[str, int]:
         self.skip_flags.append(skip)
+        self.only_missing_flags.append(only_missing)
         if skip:
             return dict(self.ZERO)
         self.llms.append(llm)