Lighter deployment artifacts

[kanej]

We should make our deployment artifacts lighter and friendlier for version control.

There are two things obvious paths forward here:

1. Make the BuildInfo files lighter. This can be done by not saving their output information.
2. Journal pruning: We should consider "compressing" the journal by pruning it after successful runs. For example, if a deployment future is executed successfully, we can replace all of its messages with a single one.