core/versioned_json_store library

Classes

VersionedJsonStore<T>: A thin, versioned JSON object store on top of StorageService's plain key-value strings — for save data with actual shape (player profile, level progress) that needs to survive a schema change between game versions without losing old players' data.
VersionedSyncConflict<T>: Both sides of a genuine VersionedJsonStore.syncWith conflict — local and cloud both have DIFFERENT data (see VersionedJsonStore.syncWith's own doc for exactly when this is raised), so picking a winner by timestamp alone risks silently discarding real progress from whichever device loses.
VersionedSyncConflictResolution<T>: What an onConflict handler decided to do about a VersionedSyncConflict — built via one of the 3 named constructors, never directly.
VersionedSyncConflictSide<T>: One side (local or cloud) of a VersionedSyncConflict — the parsed value plus the syncedAtMs timestamp it was saved under.

VersionedSyncConflictStrategy: Which side VersionedSyncConflictResolution picked.

VersionedSyncConflictHandler<T> = VersionedSyncConflictResolution<T> Function(VersionedSyncConflict<T> conflict): Caller-supplied conflict handler for VersionedJsonStore.syncWith — see that method's doc for exactly when this is invoked, and its exception-safety contract.