Renders the dream artifact: a 5x5 grid of MFV profile bar charts (one per
(hc, cc) cell), per-foundation dlogit heatmaps for MFV, per-factor C heatmaps
for ordinal instruments, and a pmass coherence heatmap. Reads the 2D-grid
profiles CSVs written by steering-lite's run_2d_grid_showcase.py.
