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.

README.md

@@ -113,6 +113,14 @@ simtrace2-pysniff-server --capture direct
 simtrace2-pysniff-server --capture disabled
 ```
 
+The GSMTAP listener also accepts the **sigrok-iso7816-stream** decoder
+(https://github.com/anttro/sigrok_iso7816_stream) — an FX2-logic-analyzer
+passive SIM sniffer that emits the same GSMTAP-SIM format on UDP 4729. Its
+custom sub-types for RST/VCC line events (`0x10`/`0x11`, added for
+compatibility with that project) are decoded as `RESET ASSERTED/DE-ASSERTED`
+and `VCC ON/OFF` timeline markers, and a reset-assert or power-removal
+correctly invalidates the file-selection tracking.
+
 Server options:
 
 ```