fix: FDR computation bug, clean up CLEAN/DALI notebooks

fix: use N=100 for FDR (matches paper), 100 trials, partial thresholds

perf: optimize FDR computation and add DALI documentation

feat: add --alpha-levels option for custom threshold computation

feat: add FNR threshold computation and partial match support

refactor: cleanup repo, add SLURM scripts, document reproducibility