hasMintedOperations

True once this document has queued a change carrying at least one operation -- local, undo/redo, or replayed from a store. Read by dev.yorkie.core.Client to decide whether this document's key takes the per-client pre-attach re-issue claim on attach or on detach. Ports yorkie-js-sdk document.ts's hasMintedOperations() (ed25355e, #1449, yorkie#2111).