Fix c19 delimiter fallback in tail_threshold_v2 reader

Add tail threshold v2 code (numeric quantile tails, no concentration)

Add tail threshold v2 code (numeric quantile tails, no concentration)

Upload Figure 6 merged preview tables

Upload Figure 6 merged preview manifest

Refresh Figure 6 tail-threshold final assets

Upload Figure 6 tail-threshold run figures

Upload Figure 6 tail-threshold final assets

Upload Figure 6 tail-threshold code bundle

Upload tail-threshold latest48 source tables and summaries

Upload tail breakdown base data

Reorganize evaluation-related folders under evaluation/