[feature] Observe variable values when attaching to ROS node

[zichunxx]

what is needed
When I attached the process to the move group node, I found that variable values in the STL vector or strings can't be watched, only the address.

why is it needed
It is intuitive and efficient to observe the value of a variable instead of the address during debugging.

Or maybe I missed some additional configurations that could be set in launch.json with ROS Attach.

Thanks!

[ooeygui]

@STAY-Melody Thanks for the issue. I honestly thought I had an issue on this already. There's a formatter I need to enable when we launch the C++ debugger. (Not sure why it isn't default).