Accept CheckpointConfig on Crew and Flow kickoff/kickoff_async/akickoff.
When restore_from is set, the entity resumes from that checkpoint.
When only config fields are set, checkpointing is enabled for the run.
Adds restore_from field (Path | str | None) to CheckpointConfig.
Write the crewAI package version into every checkpoint blob. On restore,
run version-based migrations so older checkpoints can be transformed
forward to the current format. Adds crewai.utilities.version module.
