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_docs_api.py

@@ -148,8 +148,14 @@ def test_docs_response_matches_schema_shape(admin_client, db) -> None:
     body = r.json()
     assert set(body) == {"documents"}
     for d in body["documents"]:
-        assert set(d) == {"id", "source", "path", "title", "chunks", "indexed_at"}
+        # Wire-additive (phase 106, task 05): the pre-date keys are all
+        # still there, joined by ``created_at`` (the document's creation
+        # date — the RAG view's ``Created`` column).
+        assert set(d) == {
+            "id", "source", "path", "title", "chunks", "created_at", "indexed_at"
+        }
         assert isinstance(d["chunks"], int) and d["chunks"] >= 0
+        datetime.fromisoformat(d["created_at"])  # raises if not ISO-8601
 
 
 # --------------------------------------------------------------------
@@ -198,8 +204,11 @@ def test_docs_tree_populated_shape_order_counts_summaries(admin_client, db) -> N
 
     homelab, deployments = sources
     # Wire-additive (phase 98, task 03): the pre-pending keys are all
-    # still there, joined by ``summary_pending``.
-    assert set(homelab) == {"name", "documents", "summary", "summary_pending", "children"}
+    # still there, joined by ``summary_pending`` — and (phase 106,
+    # task 05) by ``updated_at`` (the subtree's max document date, D9).
+    assert set(homelab) == {
+        "name", "documents", "updated_at", "summary", "summary_pending", "children"
+    }
     assert homelab["documents"] == 4  # the whole recursive count
     assert homelab["summary"] == "Homelab docs."  # the (source, "") row
     assert homelab["summary_pending"] is False  # the stored root row covers it
@@ -338,7 +347,10 @@ def test_docs_tree_summary_pending_on_source_and_folder_nodes(admin_client, db)
     r = admin_client.get("/api/docs/tree")
     assert r.status_code == 200
     (homelab,) = r.json()["sources"]
-    assert set(homelab) == {"name", "documents", "summary", "summary_pending", "children"}
+    # Phase 106 (task 05): ``updated_at`` joins the source node keys.
+    assert set(homelab) == {
+        "name", "documents", "updated_at", "summary", "summary_pending", "children"
+    }
     assert homelab["summary"] == "Homelab docs."
     assert homelab["summary_pending"] is False
     # Direct subfolders in path order: k8s < wiki.