Automatically wrap commands in a span

[psmoot]

It might be very handy to be able to wrap execution of a command in a span, automatically handling trace and parent IDs. We could make adding a command to a trace as easy as:
otel span <span name> find . -name *.o

This is very similar to wrapping a command in sudo or strace.

Where this gets really handy is if running a command wrapped in a span recursively wraps another command in a span. The second otel span command should automatically detect it's already in a span and set its parent span appropriately.

What I envision is otel span <name> <command> setting environment variables which get picked up by the recursive otel span commands. When an otel span <name> <command> executes and sees those variables, it knows to use the current span ID as the parent span ID and generate a new span ID.

[psmoot]

Feel free to assign this to me. I'd like to work on this. I did a prototype as a bash script and it's pretty straightforward. Learning to use the click library is going to take more work.