test(shape): shape_from_h5 round-trips a real .h5

tests/test_shape_metrics_h5.py

@@ -0,0 +1,22 @@
+import numpy as np, h5py
+from sfm.shape_metrics import shape_from_h5
+
+def _write_h5(path, chans):
+    with h5py.File(path, "w") as f:
+        g = f.create_group("samples")
+        for k, v in chans.items():
+            g.create_dataset(k, data=np.asarray(v, dtype="float32"))
+
+def test_shape_from_h5_reads_dominant_axis(tmp_path):
+    p = tmp_path / "ev.h5"
+    long = np.zeros(1024, dtype="float32"); long[100] = 0.48
+    _write_h5(p, {"Tran": np.zeros(1024), "Vert": np.zeros(1024), "Long": long,
+                  "MicL": np.ones(1024)})
+    s = shape_from_h5(str(p))
+    assert s["axis"] == "Long" and s["near_peak_count"] <= 3
+
+def test_shape_from_h5_none_on_missing_or_degenerate(tmp_path):
+    assert shape_from_h5(str(tmp_path / "nope.h5")) is None
+    p = tmp_path / "degen.h5"
+    _write_h5(p, {"Tran": np.zeros(1), "Vert": np.zeros(1), "Long": np.zeros(1)})
+    assert shape_from_h5(str(p)) is None