added capture time for every sweep

python_app/models/dataset_model.py

@@ -32,12 +32,22 @@ class ComboKey:
 
 @dataclass(slots=True)
 class TraceData:
-    """One frequency-domain trace set for a specific switch combination."""
+    """One frequency-domain trace set for a specific switch combination.
+
+    ``capture_start_ns``/``capture_end_ns`` bound the monotonic window in which
+    THIS trace's sweep was measured, excluding the switch drive and settling that
+    preceded it. In switched modes a collection is assembled combo by combo over
+    many milliseconds, so the collection-level window says nothing about when any
+    individual combo was measured — these do. Zero on both means the producer did
+    not report per-trace timing.
+    """
 
     combo: ComboKey
     frequency_hz: np.ndarray
     s11: np.ndarray
     s21: np.ndarray
+    capture_start_ns: int = 0
+    capture_end_ns: int = 0
 
 
 @dataclass(slots=True)