getStateVector = store => {
  const sm = new Map();
  store.clients.forEach((structs, client) => {
    const struct = structs[structs.length - 1];
    sm.set(client, struct.id.clock + struct.length);
  });
  return sm;
}
Return the states as a Map<client,clock>.
Note that clock refers to the next expected clock id.

@param {StructStore} store
@return {Map<number,number>}

@public
@function