fix(import): derive record_type from filename suffix instead of hardcoding "Waveform"

The BW ACH ingest path was inserting every event with
record_type="Waveform" regardless of the actual type because
read_blastware_file() had `ev.record_type = "Waveform"` hardcoded, and
the live watcher-forward path parses files from a tmp path (suffix
".bw") that doesn't carry the original extension.

V10.72+ MiniMate Plus firmware encodes the event type as the last
character of the AB0T extension scheme (H=Histogram, W=Waveform,
M=Manual, E=Event, C=Combo).  This change:

  1. Adds derive_record_type_from_filename() public helper in
     minimateplus/event_file_io.py
  2. Uses it inside read_blastware_file() so direct callers (the
     --dry-run path of scripts/import_bw.py, tests, ad-hoc scripts)
     get correct types automatically
  3. Overrides ev.record_type in WaveformStore.save_imported_bw()
     using the ORIGINAL filename (source_path.name) — required
     because the parser sees only the tmp file

Old S338 firmware (3-char extensions ending in `0`) and any
unrecognized suffix fall back to "Waveform".

Existing DB rows ingested before this fix are stuck with
record_type="Waveform" — a one-off SQL backfill would fix them
retroactively if desired.  Terra-view's event modal also derives
client-side from the filename, so the UI already shows the correct
type for old events even without the backfill.

Version bumped to 0.16.1 in pyproject.toml, event_file_io.py
TOOL_VERSION, sfm/server.py FastAPI version, and CHANGELOG.md.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

minimateplus/event_file_io.py

@@ -47,7 +47,7 @@ SIDECAR_KIND   = "sfm.event"
 # bumped without a `pip install` re-run — leading to confusing stale
 # version stamps in sidecars.  Bump this constant and CHANGELOG.md
 # together at release time.
-TOOL_VERSION = "0.16.0"
+TOOL_VERSION = "0.16.1"
 
 try:
     # Best-effort: prefer the installed metadata when it's NEWER than the
@@ -646,6 +646,50 @@ def _peaks_from_samples(samples: dict[str, list[int]]) -> PeakValues:
     )
 
 
+_RECORD_TYPE_BY_EXT_SUFFIX = {
+    'H': 'Histogram',
+    'W': 'Waveform',
+    'M': 'Manual',
+    'E': 'Event',
+    'C': 'Combo',
+}
+
+
+def derive_record_type_from_filename(filename, default: str = "Waveform") -> str:
+    """Derive a BW Event's record_type from its filename's extension suffix.
+
+    V10.72+ MiniMate Plus firmware encodes the event type as the LAST
+    character of the extension (the `T` in BW's `AB0T` scheme):
+
+        ``M529LKIQ.G10H``  →  H  →  ``"Histogram"``
+        ``T350L385.VY0W``  →  W  →  ``"Waveform"``
+        ``...M``           →  M  →  ``"Manual"``
+        ``...E``           →  E  →  ``"Event"``
+        ``...C``           →  C  →  ``"Combo"``
+
+    Old S338 firmware uses 3-char extensions ending in ``0`` whose
+    encoding is not yet known — those fall through to ``default``.
+    Micromate Series 4 uses a different scheme entirely (observed:
+    ``IDFH``, ``IDFW``) but the LAST-char convention (H / W) still holds
+    for the type code, so it works for both families.
+
+    Returns ``default`` if filename is empty, has no extension, or the
+    suffix char isn't a recognized type code.
+    """
+    if not filename:
+        return default
+    try:
+        name = Path(filename).name
+    except (TypeError, ValueError):
+        return default
+    if '.' not in name:
+        return default
+    ext = name.rsplit('.', 1)[1]
+    if not ext:
+        return default
+    return _RECORD_TYPE_BY_EXT_SUFFIX.get(ext[-1].upper(), default)
+
+
 def read_blastware_file(path: Union[str, Path]) -> Event:
     """
     Parse a Blastware waveform file into an Event.
@@ -727,7 +771,12 @@ def read_blastware_file(path: Union[str, Path]) -> Event:
     ev = Event(index=-1)
     if strt_fields.get("waveform_key"):
         ev._waveform_key = bytes.fromhex(strt_fields["waveform_key"])
-    ev.record_type     = "Waveform"
+    # Derive record_type from the filename's extension suffix (H/W/M/E/C).
+    # When called from save_imported_bw the path here is a tmp file with a
+    # ".bw" suffix, so the derivation falls back to "Waveform" and the
+    # caller overrides ev.record_type using the original filename — see
+    # waveform_store.save_imported_bw.
+    ev.record_type     = derive_record_type_from_filename(path.name)
     ev.rectime_seconds = strt_fields.get("rectime_seconds")
     ev.total_samples   = strt_fields.get("total_samples")
     ev.pretrig_samples = strt_fields.get("pretrig_samples")