fix(tests): the write-path telemetry test asserted the defect, not the split (#3497)

`assert_called_once` held only because the rule arm skipped its retrieval_logs
row when it found nothing. With the arm logging every call, the test now
asserts what it was always about — exactly one `write_path` row, no
`auto_inject`, and the rule arm keeping its own separate source.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011cPyzNnegXHr5iRMzzy5KJ

tests/test_write_path_trigger.py

@@ -360,10 +360,18 @@ async def test_telemetry_uses_its_own_source():
          patch.object(pc, "record_retrieval", rec), \
          patch.object(pc, "owner_names_for", AsyncMock(return_value={})):
         await pc.build_write_path_hint(1, "src/x.py", code=REAL_CODE, project_id=4)
-    rec.assert_called_once()
+    sources = [c.kwargs["source"] for c in rec.call_args_list]
-    assert rec.call_args.kwargs["source"] == "write_path"
+    assert sources.count("write_path") == 1, sources
-    assert rec.call_args.kwargs["source"] != "auto_inject"
+    assert "auto_inject" not in sources
-    assert rec.call_args.kwargs["project_id"] == 4
+
+    note_arm = next(c for c in rec.call_args_list if c.kwargs["source"] == "write_path")
+    assert note_arm.kwargs["project_id"] == 4
+
+    # The rule arm rides along on the same hint and logs its own call even when
+    # it finds nothing (#3497). This assertion used to be `assert_called_once`,
+    # which passed only because that row was never written — the test encoded
+    # the defect. The second row is the point of having two sources.
+    assert "write_path_rule" in sources, sources
 
 
 @pytest.mark.asyncio