docs: SOURCES.md add ## 10 UniT + ## 11 TacQuad sections, update all stale row counts (fota_unlabeled, RTM, sims, feelanyforce, etc), add Channel-order normalization section; README: update header tagline frame count

SOURCES: switch samples_100 → samples_40 (4x10 grids)

SOURCES: add authors-vs-ours RTM comparison + explain why we use seq variant

SOURCES: add sim_tactile_mnist + sim_starstruck sections, RTM/gelslam rule updates, TacQuad note

SOURCES: clarify RTM timestamp-based frame picker

Add SOURCES.md — per-subset intro, processing, stats, and 100-image samples