v0.1.2 — solo author, citation updates

v0.1.1 — multichannel, ICA, preprocessing, BIDS I/O

Move paper.md, paper.bib, and JOSS_ROADMAP.md into paper/ directory

Add gastric-brain coupling module with PLV, surrogate testing, and fM…

…RI pipeline

Implements the coupling analysis pipeline ported from the StomachBrain-MentalHealth
MATLAB pipeline (Banellis et al. 2025). Two-layer architecture:

Layer 1 (gastropy.coupling): modality-agnostic numpy-only functions
- phase_locking_value / phase_locking_value_complex
- surrogate_plv via circular time-shifting (median rotation method)
- coupling_zscore for empirical vs null comparison
- circular_mean, resultant_length, rayleigh_test

Layer 2 (gastropy.neuro.fmri): fMRIPrep-to-PLV-map convenience functions
- regress_confounds (GLM with motion + aCompCor regressors)
- bold_voxelwise_phases (bandpass + Hilbert at gastric peak frequency)
- compute_plv_map / compute_surrogate_plv_map with 3D volume reconstruction

Also adds fetch_fmri_bold() for downloading sample BOLD data via pooch,
and 54 new tests (178 total, all passing).