Provide more feedback to user on protolog to logcat command

Add some feedback to the user when they use the logcat protolog command to help understand what is going on and when the command might be failing or executing unexpectedly.

Change-Id: I69f734f5da444eaf6939bae91a0ffb76b68fbb54
Test: atest TracingTests
Flag: EXEMPT logging only
Bug: 397637453