test: fix cli mocks, add pytest config and coverage gaps

- tests/test_cli.py: fix 26 fetch_issues_with_spent_time mocks to return
  3-element tuples (issue, hours, activities) matching the real signature
- pyproject.toml: add [tool.pytest.ini_options] with testpaths and
  pythonpath so bare pytest works
- tests/test_client.py: add pagination test (>100 time entries arriving
  in pages, hours aggregated across all pages)
- tests/test_formatters.py: add structural tests — XLSX full header row
  and grand total row via openpyxl, HTML thead with all columns and
  tbody row count
- add strict xfail trap-tests for known bugs: #58 (naive created_on vs
  aware dedup cutoff TypeError) and #59 (parse_date_range rejects
  datetime range from dynamic+datetime period)

Closes #67

tests/test_client.py

@@ -691,3 +691,104 @@ def test_dedup_mixed_entries_correct_filtering(mock_redmine_class):
     assert len(result) == 2
     ids = {r[0].id for r in result}
     assert ids == {20, 30}
+
+
+# -- Пагинация time entries (>100 записей) --
+
+
+@mock.patch.dict(os.environ, PASSWORD_ENV, clear=True)
+@mock.patch("redmine_reporter.client.Redmine")
+def test_fetch_aggregates_hours_across_all_pages(mock_redmine_class):
+    """Time entries приходят страницами по 100 — часы агрегируются по всем страницам."""
+    mock_redmine = mock_redmine_class.return_value
+    _configure_current_user(mock_redmine, user_id=123)
+
+    def make_entry(issue_id, hours):
+        e = mock.MagicMock()
+        e.issue.id = issue_id
+        e.hours = hours
+        return e
+
+    # Эмулируем ленивую пагинацию redminelib ResourceSet: записи отдаются
+    # генератором порциями ("страницами" по 100), как при догрузке с сервера.
+    # Если клиент прочитает только первую страницу, агрегация будет неверной.
+    pages = [
+        [make_entry(1, 0.5) for _ in range(100)],
+        [make_entry(2, 1.0) for _ in range(100)],
+        [make_entry(1, 0.5) for _ in range(50)],
+    ]
+
+    def paged_entries():
+        for page in pages:
+            yield from page
+
+    mock_redmine.time_entry.filter.return_value = paged_entries()
+
+    mock_issue1 = mock.MagicMock()
+    mock_issue1.id = 1
+    mock_issue1.project = "P"
+    mock_issue2 = mock.MagicMock()
+    mock_issue2.id = 2
+    mock_issue2.project = "P"
+    mock_redmine.issue.filter.return_value = [mock_issue1, mock_issue2]
+
+    result = fetch_issues_with_spent_time("2026-01-01", "2026-03-31")
+
+    assert result is not None
+    hours_by_id = {issue.id: hours for issue, hours, _ in result}
+    # issue 1: 100×0.5 (стр. 1) + 50×0.5 (стр. 3) = 75.0
+    assert hours_by_id[1] == 75.0
+    # issue 2: 100×1.0 (стр. 2) = 100.0
+    assert hours_by_id[2] == 100.0
+
+
+# -- #58: дедупликация при precision=datetime с naive created_on --
+
+
+@pytest.mark.xfail(
+    strict=True,
+    reason="bug #58: naive created_on vs aware dedup cutoff raises TypeError; "
+    "fix must normalize entry datetimes to aware (UTC)",
+)
+@mock.patch.dict(os.environ, PASSWORD_ENV, clear=True)
+@mock.patch("redmine_reporter.client.Redmine")
+def test_dedup_normalizes_naive_created_on_to_utc(mock_redmine_class):
+    """python-redmine отдаёт naive created_on; cutoff aware (UTC) — фильтрация не падает.
+
+    Ожидаемое поведение после фикса #58: naive datetime трактуется как UTC,
+    старые записи отсекаются, новые сохраняются.
+    """
+    from datetime import datetime, timezone
+
+    mock_redmine = mock_redmine_class.return_value
+    _configure_current_user(mock_redmine, user_id=123)
+
+    dedup_cutoff = datetime(2026, 7, 1, 12, 0, 0, tzinfo=timezone.utc)
+
+    e_old = mock.MagicMock()
+    e_old.issue.id = 1
+    e_old.hours = 2.0
+    e_old.created_on = datetime(2026, 7, 1, 10, 0, 0)  # naive, как из python-redmine
+    e_old.updated_on = datetime(2026, 7, 1, 10, 0, 0)
+
+    e_new = mock.MagicMock()
+    e_new.issue.id = 2
+    e_new.hours = 1.0
+    e_new.created_on = datetime(2026, 7, 1, 14, 0, 0)  # naive
+    e_new.updated_on = datetime(2026, 7, 1, 14, 0, 0)
+
+    mock_redmine.time_entry.filter.return_value = [e_old, e_new]
+
+    mock_issue2 = mock.MagicMock()
+    mock_issue2.id = 2
+    mock_issue2.project = "P"
+    mock_issue2.subject = "T"
+    mock_issue2.status = "New"
+    mock_redmine.issue.filter.return_value = [mock_issue2]
+
+    result = fetch_issues_with_spent_time(
+        "2026-07-01", "2026-07-01", dedup_before=dedup_cutoff
+    )
+
+    assert result is not None
+    assert [r[0].id for r in result] == [2]