sparkengine-persistence-save-and-migrations

What problem does it solve? Game state persistence bugs in SparkEngine — corrupt save files, failed loads, torn database flushes, and unsafe format migrations — are hard to diagnose without knowing which of the four persistence layers is involved and what durability guarantees each one actually provides. ## Core Features & Use Cases - Save format reference: Documents the .spark_save binary layout (SPRK magic, version 3, reader window 1..3), parser budgets, slot retention, and atomic write semantics. - Durability status matrix: Tracks which persistence claims are implemented, tested, CI-enforced, or still open (e.g., AsyncDatabase torn flush, missing N-1 migration fixtures under SAVE-230/DATA-120). - Failure-mode triage: Maps symptoms like failed loads, stuck futures, and quarantined .corrupt-*.bak files to likely causes and first diagnostic moves. - Use Case: A player reports their save won't load after an update. Use this Skill to check the version gate, identify whether the file hit a parser budget or truncation rejection, and determine whether a migration step is missing. ## Quick Start Ask the AI to diagnose why a SparkEngine save file fails to load or to review the durability of a new persistence store before committing it.