refactor(tests): one definition each for the copied fixtures and fakes (#2825, milestone 296 area 1)

The shape ledger showed the same test scaffolding defined over and over:
_bind_user x12 (byte-identical), _dispose_engine x10 in three wordings,
_no_supersession x3, _make_mock_session x7 in three subsets, a get-or-create
User helper x2 (+3 inlined), and fifteen hand-rolled MagicMock note factories
each re-explaining the same "an auto-MagicMock attribute is truthy" hazard
(note 2109).

Now: conftest.py carries _bind_user / _dispose_engine / _no_supersession as
opt-in fixtures (pytestmark = usefixtures(...) per module, so unit tests pay
nothing), and tests/helpers.py carries make_mock_session(), ensure_user() and
fake_note(**attrs) — the hazard documented once, real values on every
attribute the product reads. Call sites were rewritten by AST so titles with
dashes and commas survived; the three SimpleNamespace _note stand-ins that
only feed a single function stay local.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tests/test_services_notes_process.py

@@ -5,13 +5,7 @@ Mocks async_session — no real DB, matching the other notes-service tests.
 from unittest.mock import AsyncMock, MagicMock, patch
 
 import pytest
-
-
-def _make_mock_session():
-    s = AsyncMock()
-    s.__aenter__ = AsyncMock(return_value=s)
-    s.__aexit__ = AsyncMock(return_value=False)
-    return s
+from tests.helpers import fake_note, make_mock_session
 
 
 def _result(first=None, all_=None):
@@ -22,17 +16,10 @@ def _result(first=None, all_=None):
     return r
 
 
-def _note(id, title):
-    n = MagicMock()
-    n.id = id
-    n.title = title
-    return n
-
-
 @pytest.mark.asyncio
 async def test_resolve_process_by_numeric_id():
-    note = _note(5, "Drift Audit")
-    session = _make_mock_session()
+    note = fake_note(id=5, title="Drift Audit")
+    session = make_mock_session()
     # numeric id → first execute (id lookup) hits
     session.execute = AsyncMock(side_effect=[_result(first=note)])
     with patch("scribe.services.notes.async_session") as cls:
@@ -46,8 +33,8 @@ async def test_resolve_process_by_numeric_id():
 
 @pytest.mark.asyncio
 async def test_resolve_process_exact_title_beats_substring():
-    note = _note(7, "Drift Audit")
-    session = _make_mock_session()
+    note = fake_note(id=7, title="Drift Audit")
+    session = make_mock_session()
     # non-digit → exact-title query (first execute) hits; substring never runs
     session.execute = AsyncMock(side_effect=[_result(first=note)])
     with patch("scribe.services.notes.async_session") as cls:
@@ -61,9 +48,9 @@ async def test_resolve_process_exact_title_beats_substring():
 
 @pytest.mark.asyncio
 async def test_resolve_process_substring_returns_candidates():
-    n1 = _note(7, "Drift Audit Remediation")
-    n2 = _note(9, "Drift Audit Notes")
-    session = _make_mock_session()
+    n1 = fake_note(id=7, title="Drift Audit Remediation")
+    n2 = fake_note(id=9, title="Drift Audit Notes")
+    session = make_mock_session()
     # exact miss, then substring returns two (most-recent first)
     session.execute = AsyncMock(side_effect=[_result(first=None), _result(all_=[n1, n2])])
     with patch("scribe.services.notes.async_session") as cls:
@@ -77,7 +64,7 @@ async def test_resolve_process_substring_returns_candidates():
 
 @pytest.mark.asyncio
 async def test_resolve_process_no_match():
-    session = _make_mock_session()
+    session = make_mock_session()
     session.execute = AsyncMock(side_effect=[_result(first=None), _result(all_=[])])
     with patch("scribe.services.notes.async_session") as cls:
         cls.return_value = session