STATUS list entries: suppress raw hex when empty, describe FCP data

- decode.py: _build_summary emits 'Data: N bytes — FCP of <file> (...)' for
  STATUS responses with data (FCP already decoded into decoded.response);
  _fcp_brief builds the 'FCP of MF (DF or ADF)' / 'FCP of EF_xxx (...)'
  fragment
- index.html: cmd_description suppresses the raw-hex fallback for
  body-less STATUS rows (nothing to describe beyond type + SW)
- tests: no-data STATUS summary None; DF/EF FCP summaries; pluralization
- Bump 1.22.19, SW cache v50->v51

simtrace2_pysniff/__init__.py

@@ -6,7 +6,7 @@ from .gsmtap import GsmtapSender, GsmtapReceiver
 from .pcap import PcapWriter
 from .dump import FileDumper, format_message
 
-__version__ = '1.22.18'
+__version__ = '1.22.19'
 __all__ = [
     'SniffSession',
     'DeviceDisconnected',