Fix EF_SPDI decode crash: parse inner '80' TLVs, emit dict plmns

stk_test1 msg 14036 regression: READ BINARY of EF_SPDI returned
"No decoded data available" — _decode_spdi (added v1.16.0) parsed
the A3 container value as bare 3-byte records (missing the inner
'80' value TLVs) and returned a list of strings, while
_build_summary/_file_summary expects the EF_PLMNwAcT shape
(list of {mcc, mnc} dicts). The resulting TypeError aborted the
whole message decode — this was the source of the 28 "Decode
error ... string indices" messages seen across all sessions.

_decode_spdi now unwraps inner '80' TLVs (bare-records fallback
kept) and always returns {'plmns': [{mcc, mnc}...]}. Replay of all
33 sessions: decode exceptions 28 → 0 (2 remaining undecoded tpdu
are 1-byte truncated capture records, not decodable by nature).

Tests: +3 (standard inner-80 form, bare-records fallback, exact
stk_test1 regression via decode_message). 344 total. Version
1.17.1, SW cache simtrace-analyser-v25.

tests/test_pcap_import.py

@@ -197,7 +197,7 @@ class TestImportEndpoint(unittest.TestCase):
 class TestVersion(unittest.TestCase):
     def test_package_version(self):
         from simtrace2_pysniff import __version__
-        self.assertEqual(__version__, '1.17.0')
+        self.assertEqual(__version__, '1.17.1')
 
     def test_status_includes_version(self):
         import os