Decode sigrok-iso7816-stream RST/VCC line events (GSMTAP 0x10/0x11)

Support the sigrok-iso7816-stream decoder (FX2 logic-analyzer passive
SIM sniffer, github.com/anttro/sigrok_iso7816_stream) which streams
GSMTAP-SIM on UDP 4729 and adds two custom sub-types for line events.

- gsmtap.py: GSMTAP_SIM_RST_EVENT (0x10) / GSMTAP_SIM_VCC_EVENT (0x11).
- capture.py: gsmtap_msg_type() maps 0x10→'rst', 0x11→'vcc' (shared by
  the listener and tests); pcap.py _SUB_TYPE_NAMES gains the same
  entries so PCAP re-imports of these captures preserve the events.
- decode.py: decode_line_event() decodes [direction, level, reserved]
  into reset asserted/de-asserted or power applied/removed + level;
  routed through decode_sniff_msg.
- database.py: reset-assert and power-removal invalidate the per-channel
  file selection (card-level transition); de-assert / power-on are
  markers only.
- frontend: RST/VCC labels (RESET ASSERTED / VCC OFF, …), a detail-view
  branch (Event + Level + raw), and list styling (.apdu-type.rst/.vcc).

README notes the custom sub-type compatibility. Tests: +8 (line-event
vectors, sniff routing, subtype + PCAP round-trip mappings) — 359
total. Version 1.21.0, SW cache simtrace-analyser-v31.

tests/test_pcap_import.py

@@ -9,7 +9,9 @@ from simtrace2_pysniff.pcap import (
     build_pcap, parse_pcap, parse_pcapng, wrap_gsmtap, extract_gsmtap,
     LINKTYPE_ETHERNET,
 )
-from simtrace2_pysniff.gsmtap import build_gsmtap_packet, GSMTAP_SIM_ATR, GSMTAP_SIM_APDU
+from simtrace2_pysniff.gsmtap import (build_gsmtap_packet, GSMTAP_SIM_ATR,
+                                      GSMTAP_SIM_APDU, GSMTAP_SIM_RST_EVENT,
+                                      GSMTAP_SIM_VCC_EVENT)
 
 
 def _gsmtap_hdr(sub_type):
@@ -54,6 +56,19 @@ class TestParsePcap(unittest.TestCase):
             (2.5, 'tpdu', b'\x80\xf2\x00\x00\x00'),
         ])
 
+    def test_roundtrip_line_events(self):
+        # sigrok-iso7816-stream custom sub-types survive a PCAP round-trip.
+        packets = [
+            (_gsmtap_hdr(GSMTAP_SIM_RST_EVENT), b'\x01\x00\x00', 1.0),
+            (_gsmtap_hdr(GSMTAP_SIM_VCC_EVENT), b'\x00\x00\x00', 1.5),
+        ]
+        data = build_pcap(packets)
+        parsed = [(round(ts, 1), t, payload) for ts, t, payload in parse_pcap(data)]
+        self.assertEqual(parsed, [
+            (1.0, 'rst', b'\x01\x00\x00'),
+            (1.5, 'vcc', b'\x00\x00\x00'),
+        ])
+
     def test_no_gsmtap(self):
         # A packet that is not GSMTAP-SIM yields nothing.
         frame = wrap_gsmtap(b'\x03' + b'\x00' * 15)  # type=3, not SIM
@@ -197,7 +212,7 @@ class TestImportEndpoint(unittest.TestCase):
 class TestVersion(unittest.TestCase):
     def test_package_version(self):
         from simtrace2_pysniff import __version__
-        self.assertEqual(__version__, '1.20.2')
+        self.assertEqual(__version__, '1.21.0')
 
     def test_status_includes_version(self):
         import os