5A: treat partial end-of-stream byte as graceful stream termination

When the device finishes streaming waveform data, it sends a single
partial byte (raw_bytes=1) rather than a complete A5 frame, then goes
silent for the full 120s timeout.

Observed: 35 chunks succeed, chunk 36 times out with raw_bytes=1 —
identical for both events in the test run.

Fix: on TimeoutError, if bytes_fed > 0 and we already have collected
frames, treat it as natural end-of-stream and break to the termination
step rather than propagating the exception.  True transport failures
(raw_bytes=0, no prior frames) still raise.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

minimateplus/protocol.py

@@ -522,10 +522,21 @@ class MiniMateProtocol:
             try:
                 rsp = self._recv_one(expected_sub=rsp_sub, reset_parser=False)
             except TimeoutError:
+                raw = self._parser.bytes_fed
                 log.warning(
                     "5A TIMEOUT chunk=%d counter=0x%04X raw_bytes=%d",
-                    chunk_num, counter, self._parser.bytes_fed,
+                    chunk_num, counter, raw,
                 )
+                if raw > 0 and frames_data:
+                    # Device sent a partial byte (likely a bare DLE/ETX end-of-stream
+                    # signal) but never completed a full frame.  Treat as graceful
+                    # stream end and fall through to the termination step.
+                    log.warning(
+                        "5A end-of-stream detected at chunk=%d (raw_bytes=%d, "
+                        "frames_collected=%d) — proceeding to termination",
+                        chunk_num, raw, len(frames_data),
+                    )
+                    break
                 raise
 
             log.warning(