[main] Block-log leap-util subcommand refactoring

[vladtr]

This PR addresses following issues:

• flags and options made applicable to actual subcommands using them
• "default" behavior of printing log changed to a subcommand print-log. Default handler of parent subcommand "block-log" eliminated
• simplified and unified callbacks and error handling for return codes and exceptions
• re-enabled (and tested) smoke-test subcommand
• few other minor fixes

[heifner]

@766C6164 should this target release/3.2?

[vladtr]

@766C6164 should this target release/3.2?

Thank you! I added this for 3.2: #327

[linh2931]

You should discard this one. After #327 is approved, merge release/3.2 to main and create a new PR on main.