Summary

• tighten MATLAB-exactness behavior for SignalObj and nspikeTrain
• extend MATLAB gold fixtures for makeCompatible, restore semantics, and burst summaries
• refresh class fidelity notes for the stronger fixture coverage

Verification

• pytest -q tests/test_matlab_gold_fixtures.py tests/test_nspiketrain_fidelity.py tests/test_signalobj_fidelity.py tests/test_class_fidelity_audit.py tests/test_parity_report.py
• python tools/notebooks/run_notebooks.py --group full --topics SignalObjExamples,nSpikeTrainExamples --timeout 900