Currently, replay events are sent from the replay package in a somewhat "custom" way, buy accessing a bunch of private methods on the hub etc.

We should refactor this so that the replay event types are part of the general API, and so that the replay package can use public APIs for everything.

• ref(replay): Avoid using private hub._withClient #6494
• fix(replay): Replace _waitForError with recordingMode #6489
• feat(core): Add scope.getLastBreadcrumb() #6495
• feat(core): Expose prepareEvent util function #6517
• ref(replay): Stop calling _updateSessionFromEvent #6510