feat(02-03): apply module-level pytestmark to 37 test files

- Add pytestmark = [pytest.mark.<category>] to all 23 root test files and 14 e2e test files
- Marker distribution: 22 unit, 7 integration, 1 blackbox, 1 sitl, 5 e2e + 2 e2e integration
- Add import pytest to test_models.py, test_download.py, test_synthetic_adapter.py (were missing)
- Convert test_sitl_integration.py's bare pytestmark to list form preserving skipif guard
- Union of all 5 markers = 298/298 = 100% coverage; 216 tests pass with --strict-markers

tests/e2e/test_coord.py

@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.coord import ecef_to_wgs84, euler_to_quaternion
 
 # --- ECEF → WGS84 ---

tests/e2e/test_dataset_base.py

@@ -2,6 +2,8 @@
 
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.datasets.base import (
     DatasetAdapter,
     DatasetCapabilities,

tests/e2e/test_download.py

@@ -3,6 +3,10 @@
 import hashlib
 from pathlib import Path
 
+import pytest
+
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.download import (
     DATASET_REGISTRY,
     DatasetSpec,

tests/e2e/test_euroc.py

@@ -13,6 +13,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.e2e]
+
 from gps_denied.testing.datasets.euroc import EuRoCAdapter
 from gps_denied.testing.harness import E2EHarness
 from gps_denied.testing.metrics import absolute_trajectory_error

tests/e2e/test_euroc_adapter.py

@@ -4,6 +4,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.datasets.base import (
     DatasetNotAvailableError,
     PlatformClass,

tests/e2e/test_euroc_mh_all.py

@@ -17,6 +17,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.e2e]
+
 from gps_denied.testing.datasets.euroc import EuRoCAdapter
 from gps_denied.testing.harness import E2EHarness
 from gps_denied.testing.metrics import absolute_trajectory_error

tests/e2e/test_euroc_vo_only.py

@@ -20,6 +20,8 @@ import cv2
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.e2e]
+
 from gps_denied.core.vo import ORBVisualOdometry
 from gps_denied.schemas import CameraParameters
 from gps_denied.testing.datasets.euroc import EuRoCAdapter

tests/e2e/test_harness_smoke.py

@@ -7,6 +7,8 @@ Correctness of VO on synthetic is out of scope — that's unit-test territory.
 
 import pytest
 
+pytestmark = [pytest.mark.integration]
+
 from gps_denied.testing.datasets.synthetic import SyntheticAdapter
 from gps_denied.testing.harness import E2EHarness, HarnessResult
 

tests/e2e/test_mars_lvig.py

@@ -4,6 +4,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.e2e]
+
 from gps_denied.testing.datasets.mars_lvig import MARSLVIGAdapter
 from gps_denied.testing.harness import E2EHarness
 

tests/e2e/test_mars_lvig_adapter.py

@@ -4,6 +4,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.datasets.base import (
     DatasetNotAvailableError,
     PlatformClass,

tests/e2e/test_metrics.py

@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.metrics import (
     absolute_trajectory_error,
     relative_pose_error,

tests/e2e/test_synthetic_adapter.py

@@ -1,8 +1,11 @@
 """SyntheticAdapter produces a deterministic straight-line trajectory."""
 
 import numpy as np
+import pytest
 
 from gps_denied.testing.datasets.base import PlatformClass
+
+pytestmark = [pytest.mark.unit]
 from gps_denied.testing.datasets.synthetic import SyntheticAdapter
 
 

tests/e2e/test_vpair.py

@@ -8,6 +8,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.e2e]
+
 from gps_denied.testing.datasets.vpair import VPAIRAdapter
 from gps_denied.testing.harness import E2EHarness
 from gps_denied.testing.metrics import absolute_trajectory_error

tests/e2e/test_vpair_adapter.py

@@ -10,6 +10,8 @@ from pathlib import Path
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.datasets.base import (
     DatasetNotAvailableError,
     PlatformClass,