nextDot

Returns the next Dot for replica to mint for a new local operation.

Precondition — one DotContext per logical replica. The returned dot is globally unique within the causal history of this DotContext. Two independently-constructed DotContext instances for the same replica will both compute seq = 1 for their first dot — producing a collision. Every causal CRDT that depends on dot uniqueness (ORSet, MVRegister, ORMap) will produce wrong results if two events share the same (replica, seq).

In practice: create exactly one DotContext per logical replica and thread it through all of that replica's operations for its lifetime.