Fig 2 (univariate decoding):
- Replace fill_between CI shading with thin CI *lines* matching MATLAB
- Increase decoded/actual linewidth to 4 (was 2) matching MATLAB
- Add ylabel "Stimulus" and increase title fontsize to 18

Fig 3 (reach setup):
- Use unfilled circle markers for Start/Finish (MATLAB default)

Fig 4 (PPAF goal vs free):
- Add Start/Finish unfilled circle markers with legend on 2D path

Fig 5 (hybrid setup):
- Use unfilled circle markers for Start/Finish
- Add Start/Finish legend on reach path subplot

Fig 6 (hybrid decoding summary):
- Overlay all 20 individual simulation traces as thin dashed lines
  (matching MATLAB's in-loop plotting of S_est, X_est, MU_est)
- Plot thick solid mean traces on top (matching MATLAB post-loop code)
- Add Start/Finish unfilled markers and legend on 2D reach path
- Set state axis ylim to [0.5, 2.5] matching MATLAB

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>