Dump additional information when the debugger crashes

[st0012]

Your proposal

When the debugger crashes for any reason, it only prints stacktrace of the exception. I think it'd be great to dump additional debugger information like:

1. The recent commands (the last 5?)
2. Depends on which component crashes
   • Session can print the last event payload it received
   • ThreadClient can print the last action payload it received
3. Configs like could affect debugger's internal states, like
   • fork_mode
   • postmortem