phase: 106_document_dates

Everything is verified green. Final report:

**Phase 106 — Document dates (final verification pass; all 10 tasks already complete)**

- Verified all phase artifacts: alembic `0020` (dev DB at `0020`), `doc_dates.py`, git `file_commit_dates`, importer `doc_dates_by_root`/`dates_updated`, both entry-point wirings, date APIs + tree `created_at`/`updated_at`, LLM surfaces (prompt block, `read` line 2, appended `ls` field), `apply_recency_boost` in `retrieve()`, UI columns/badge, admin editor, mock-LLM regex — all present and correct; no defects found, no fixes needed.
- `uv run pytest --cov=app --cov-report=term-missing` → **2299 passed, TOTAL 99%** (>90% ✓)
- `uv run pytest tests/e2e/test_document_dates.py -v --no-cov` → **6/6 passed** in isolation (DB up)
- 12 regression E2E suites (retrieval_quality, whole_document_context, agent_document_tools, ls_tree_drilldown, read_truncation_cap, kb_tree, kb_tree_nav, document_viewer, edit_summaries, import_documents, sync_button, hidden_folders_toggle, smoke) → **all green in isolation**
- `uv run ruff check .` → clean; `uv run pyright` → **0 errors, 0 warnings**

**Completion criteria:** 1) non-null `created_at` + 0020 upgrade/downgrade on dev DB ✓ (real-Alembic integration tests) 2) sync refresh/older/manual-persists/content-reset/no sources_meta bump ✓ 3) zip/tar mtime + future→today ✓ 4) LLM date surfaces + cross-check ✓ 5) UI Created/Updated/badge positions ✓ 6) admin editor set+revert round-trip ✓ 7) old-correct-beats-new-similar (defaults & boost-off) + near-tie + `BOR_RECENCY_BOOST=0` byte-identical ✓ 8) full gate ✓ 9) commit/phase-move — left to harness per instructions.

- **Notable:** recency default tuned 0.001 → **0.0007** (task 07 step 5 explicitly permits; measured margins recorded in `test_recency_boost.py` docstring).
- **Next pending phase:** none — `todo/` holds only this phase.

tests/integration/test_sync_api.py

@@ -268,6 +268,11 @@ class FakeImportSources:
         # keying; a shared-root collision ORs — if either row says
         # "index hidden", the root does).
         self.include_hidden_maps: list[dict[str, bool]] = []
+        # Phase 106: the per-root source-date map the runner builds
+        # from ``file_commit_dates`` after each git clone (git rows
+        # only, same root-string keying; local rows contribute
+        # nothing).
+        self.doc_dates_maps: list[dict[str, dict[str, datetime]]] = []
 
     async def __call__(
         self,
@@ -280,6 +285,7 @@ class FakeImportSources:
         progress: Callable[[str, str, int, int], None] | None = None,
         ignore_by_root: dict[str, list[str]] | None = None,
         include_hidden_by_root: dict[str, bool] | None = None,
+        doc_dates_by_root: dict[str, dict[str, datetime]] | None = None,  # phase 106
     ) -> ImportSummary:
         self.sources.append(list(sources))
         self.llms.append(llm)
@@ -287,6 +293,7 @@ class FakeImportSources:
         self.progress_hooks.append(progress)
         self.ignore_maps.append(ignore_by_root or {})
         self.include_hidden_maps.append(include_hidden_by_root or {})
+        self.doc_dates_maps.append(doc_dates_by_root or {})
         if self.delay:
             await asyncio.sleep(self.delay)
         return self.summary
@@ -453,9 +460,14 @@ def test_admin_sync_success_reports_full_detail(
     assert body["detail"] == {
         "files": 5, "added": 1, "updated": 2, "unchanged": 2, "pruned": 3,
         "errors": 0, "chunks": 11, "summaries": 1, "summary_errors": 0,
+        "dates_updated": 0,  # phase 106: additive key, after summary_errors
         "overview": True,
         "sources_version": 1,  # phase 53: changed KB → exactly one bump (0 → 1)
     }
+    # Phase 106: the runner feeds the per-root date map — the fake
+    # checkout is not a git repo, so ``file_commit_dates`` fails soft
+    # to ``{}`` for the one git row (root-keyed).
+    assert fake_import.doc_dates_maps == [{str(tmp_path / "bor" / "repo"): {}}]
     # The bump committed: the counter advanced exactly once, not twice.
     assert current_sources_version(db) == 1
     # Git: the configured repo was cloned into BOR_SOURCES_DIR/<repo-name>/.
@@ -607,6 +619,7 @@ class _GatedImport:
         progress: Callable[[str, str, int, int], None] | None = None,
         ignore_by_root: dict[str, list[str]] | None = None,
         include_hidden_by_root: dict[str, bool] | None = None,
+        doc_dates_by_root: dict[str, dict[str, datetime]] | None = None,  # phase 106
     ) -> ImportSummary:
         if progress is not None:
             progress("repo", "notes/deep.md", 1, 3)
@@ -1148,6 +1161,7 @@ def test_import_error_is_reported_with_credentials_masked(
         progress: Callable[[str, str, int, int], None] | None = None,
         ignore_by_root: dict[str, list[str]] | None = None,
         include_hidden_by_root: dict[str, bool] | None = None,
+        doc_dates_by_root: dict[str, dict[str, datetime]] | None = None,  # phase 106
     ) -> ImportSummary:
         raise EmbeddingError(
             "embeddings request to https://user:secret@aipi.reeseapps.com/v1 "