CDN-371: The Tidal Spectrum Gate

CDN-371 tests whether the temporal spectrum of a trace-free tidal field changes two-body coherence under matched tensor amplitude. Using the same dimensionless two-body contrast framework as CDN-370, this artifact holds the 3D trace-free tensor RMS fixed while varying only the time structure of the environmental tidal field: static, fast OU, mid OU, slow OU, periodic, bursty, and mixed spectra. The result shows that matched amplitude does not erase temporal memory: capture fractions at C0=0.65 span from 0.145 to 0.998, demonstrating that correlation time, coherent rotation, and intermittency are independent physics knobs. The release includes simulation code, spectrum sweeps, time-series samples, PSD figures, trajectory projections, prediction hashes, and validation notes.