fix(protocol): refine extra chunk fetching logic for accurate termination response

sfm/server.py

@@ -885,21 +885,17 @@ def device_event_blastware_file(
         def _do():
             with _build_client(port, baud, host, tcp_port, timeout=120.0) as client:
                 info = client.connect()
-                # Download extra chunks after "Project:" until the footer marker
-                # 0x0e 0x08 is detected in a chunk tail.  The cap prevents
-                # accidentally downloading into post-event silence.
-                # Cap = rectime * 4 + 4 covers up to ~10 sec events safely.
-                rectime = 1.0
-                try:
-                    rectime = float(info.compliance_config.record_time or 1.0)
-                except (AttributeError, TypeError, ValueError):
-                    pass
-                extra_chunks = max(4, int(rectime * 6) + 8)  # generous cap; silence detection stops early
-                log.info("blastware_file: rectime=%.1fs → extra_chunks_cap=%d", rectime, extra_chunks)
+                # Use full_waveform=True (stop_after_metadata=False) so the device
+                # streams until it naturally signals end-of-stream (1-raw-byte signal).
+                # BW does the same — the ACH download and manual pull both let the device
+                # determine when to stop.  The termination response at that point contains
+                # the correct 0e 08 footer with monitoring timestamps.
+                # For Continuous/Single-Shot events, end-of-stream comes after the real
+                # ADC data (not after 35+ silence chunks as in Histogram+Continuous mode).
+                # max_chunks=32 is a safety cap; natural end-of-stream stops much earlier.
                 events = client.get_events(
-                    full_waveform=False,
+                    full_waveform=True,
                     stop_after_index=index,
-                    extra_chunks_after_metadata=extra_chunks,
                 )
                 matching = [ev for ev in events if ev.index == index]
                 return matching[0] if matching else None, info