Return results when the algorithms finish

[hccz95]

I have made some minor adjustments to the existing code. These changes do not alter any current logic or produce any side effects. The only purpose of these modifications is to allow run_cc.py, as well as run_il and run_vd, to return the results after the algorithm's execution.
The returning results provides users with additional information like:

1. log directory: results.trials[0].logdir
2. best checkpoint directory: results._checkpoints[0]['checkpoint_manager']._best_checkpoints[0].value.value
3. newest checkpoint directory: results._checkpoints[0]['checkpoint_manager'].newest_checkpoint.value
4. and etc.