some kamil_adc fixes

python_app/workflows/sequential_capture_workflow.py

@@ -187,6 +187,16 @@ class SequentialCaptureSession:
         if self._config.runtime.settling_ms > 0:
             time.sleep(self._config.runtime.settling_ms / 1000.0)
 
+        # A free-running streaming radar (Kamil ADC) keeps a sweep captured in the
+        # previous combination buffered, and may have a transition-straddling sweep
+        # in flight. Drop those so this capture holds data from the new switch state
+        # — otherwise the trace is labelled with this combo but carries the previous
+        # one's data (an off-by-one across the sequence). Discrete radars (LibreVNA)
+        # acquire a fresh sweep per call and expose no such method, so skip them.
+        drain_after_switch = getattr(self._radar, "drain_after_switch", None)
+        if callable(drain_after_switch):
+            drain_after_switch()
+
         sweep_traces: list[TraceData] = []
         for _ in range(self._median_sweep_count):
             sweep = self._radar.acquire()