There are several things to know here.
1. Firstly, when the CLI is run by the IDE, the right part of the tool window view doesn't show the interactive elements of the CLI. The CLI effectively runs in non-interactive mode.
2. Now, here, I don't think the CLI is even called at all. We usually have special integrations for these parts, and they report the progress natively in the tree view on the left.
3. I don't think there are any details yet for this phase. This is an extra phase of dependency resolution to download the sources jars of your dependencies. We're currently looking into how we can integrate dependency resolution into our progress system.
Note that this phase is not really part of the sync itself, it's a background step after the sync. You can already use the project before this.