MutationKey

Identifies the logical mutation being made, independent of when it was enqueued.

MutationQueue coalesces by key: enqueueing a mutation under a key that already has one pending or retrying replaces it, so rapidly toggling the same logical state (e.g. liking then unliking video 42 before the first call lands) collapses to a single call for the latest desired state instead of replaying every intermediate one.

Construct one per logical target, e.g. MutationKey("like:video:42") or via of.