Point substrate README at OpenMHC HF Space (drop website URL)

Replace stale 16-method docs with 17-method variant

Replace stale 16-method docs with 17-method variant

Cross-link to bootstrap_with_dense_weekly/ + top-level substrate SCHEMA

Cross-link to bootstrap_with_dense_weekly/ sibling

Add per-method substrate SCHEMA (incl. fallback_rate sidecar field)

Add per-method substrate README (imputation/<m>.parquet + sidecar)

Add/update imputation metadata: mean

Add/update imputation metadata: mean

Add fallback_rate=0.000000 to lsm2_weekly.meta.json

Add fallback_rate=0.000000 to lsm2_weekly_sparse.meta.json

Add fallback_rate=0.000000 to lsm2.meta.json

Add fallback_rate=0.000000 to timesnet.meta.json

Add fallback_rate=0.000000 to fedformer.meta.json

Add fallback_rate=0.000000 to dlinear_weekly.meta.json

Add fallback_rate=0.000000 to dlinear.meta.json

Add fallback_rate=0.000000 to brits.meta.json

Add fallback_rate=0.000000 to personalized_temporal_mean.meta.json

Add fallback_rate=0.000000 to personalized_mode.meta.json

Add fallback_rate=0.000000 to personalized_mean.meta.json

Add fallback_rate=0.000000 to temporal_mode.meta.json

Add fallback_rate=0.000000 to temporal_mean.meta.json

Add fallback_rate=0.000000 to linear.meta.json

Add fallback_rate=0.000000 to locf.meta.json

Add fallback_rate=0.000000 to mode.meta.json

Add fallback_rate=0.000000 to mean.meta.json

Sync docs for imputation/bootstrap_with_dense_weekly

Sync docs for imputation/bootstrap_with_dense_weekly

Add 17-method (with lsm2_weekly dense) bootstrap: draws.meta.json

Add 17-method (with lsm2_weekly dense) bootstrap: draws.parquet

Add/update imputation bootstrap reference: draws.meta.json

Add/update imputation bootstrap reference: draws.parquet

Add/update imputation metadata: lsm2_weekly

Add/update imputation substrate: lsm2_weekly

Add/update imputation substrate: lsm2_weekly_sparse

Add/update imputation substrate: lsm2

Add/update imputation substrate: fedformer

Add/update imputation substrate: dlinear

Add/update imputation substrate: brits

Set method types to paper categorization (Statistical / Neural)

Add subtrack (single-day / long-context) to method sidecars

Seed display metadata sidecars for the 16 reference methods

Add imputation/bootstrap/SCHEMA.md

Add imputation/bootstrap/README.md

Drop redundant pooled per_user_errors meta

Drop redundant pooled per_user_errors (concat of per-method files)

Add/update imputation bootstrap reference: per_user_errors.meta.json

Add/update imputation bootstrap reference: per_user_errors.parquet

Add/update imputation bootstrap reference: draws.meta.json

Add/update imputation bootstrap reference: draws.parquet