Hydrate accepted producer checkpoints

docs/internal/state.md

@@ -43,6 +43,17 @@ not permit stale downstream reuse. The CLI's selective recomputation policy
 records `forced_recompute` for the selected step and its dependents while
 requiring compatible predecessor checkpoints.
 
+Ordinary resume loads extract, merge, and normalize checkpoints progressively
+and may execute later lane stages after an earlier cache miss. Selective
+recomputation instead asks the loader for the required producer's accepted
+normalize artifact. That lookup reuses the existing normalize files, requires
+workspace schema v3 plus an exact non-empty invocation identity, and deliberately
+does not require extract or merge checkpoint files or dependency fingerprints.
+The runner performs canonical codec and producer-provenance validation before
+cloning the artifact into normal step output. Success restores only stored
+normalize warnings and emits one normalize decision; failure retains the files,
+records the decision, and stops without executing the producer or consumer.
+
 The loader assigns a typed category and reason code at each validation site;
 diagnostic prose is not classified after the fact. The runner then applies
 forced-execution policy, validates reusable artifact bytes through the prepared