fix: hydrate download uses 1-indexed release assets → 0-indexed local paths GitHub release assets: shard-01.bgz7 through shard-04.bgz7 (1-indexed) Local storage + manifest SHA256: shard-00.bgz7 through shard-03.bgz7 (0-indexed) Verified: qwen35-9b-base + qwen35-9b-distilled, all 8 shards SHA256 OK. https://claude.ai/code/session_01Y69Vnw751w75iVSBRws7o7#77