[compass_app] Fix Command<T> to capture action exceptions as Result<T> - #2889

The Command<T> action return was not captured as Result<T> when the action throws.

• the fix will make Command<T>'s action always return a Result<T>
• an additional test added to the test/utils/command_test.dart to verify the fix

Pre-launch Checklist

• I read the [Flutter Style Guide] recently, and have followed its advice.
• I signed the [CLA].
• I read the [Contributors Guide].
• I have added sample code updates to the [changelog].
• I updated/added relevant documentation (doc comments with ///).