User asked the right question: do events without 30 NN blocks decode
fully? Answer: YES.
event-a: Tran 3328 ✓ Vert 3328 ✓ Long 3328 ✓ (28 segments, 0 '30 NN')
event-c: Tran 1280 ✓ Vert 1280 ✓ Long 1280 ✓ (12 segments, 0 '30 NN')
event-d: Tran 1280 ✓ Vert 1280 ✓ Long 1280 ✓ (12 segments, 0 '30 NN')
17,664 ADC samples decoded byte-exact against BW's ASCII export.
Zero divergences across event-a, event-c, event-d.
This means the codec is FULLY SOLVED for any event without 30 NN
blocks. The remaining gap is the 30 NN block format only — used for
high-amplitude regions where deltas exceed int8 range. For quiet
events (or quiet stretches of loud events), the decoder is complete.
9 new regression tests bring the total to 55, all passing.
Files: tests/test_waveform_codec.py + docs/waveform_codec_re_status.md
+ new analysis/verify_quiet_bundle.py.