[debugger] Ability to execute statements at breakpoint and analyze results of data returning statements

Hey all, I am not sure if this is really the right place to ask/propose
this or not, but I thought i'd give it a shot. If nothing else I can be
pointed to the correct place.

Let me preface this with: I am not at all familiar with the underlying code
of the debugger, how it interacts with Postgres, or what the UI layer is
able to do with it that it isn't already doing.

I was wondering what kind of control there is to send over statements while
execution is paused at a breakpoint to give the ability to analyze data as
it is for the connection the function is running on in whatever state it
may be in.

That is one of the main things that I noticed when using the debugger is
it's still not all that useful for a lot of the functions I write because a
lot of times they don't contain all that much procedural code, but do
contain a lot of temp tables, and data processing using sql. It would be
amazing to set a breakpoint and be able to step through the function, while
having the ability to look at what the data looks like in any table after
each step.

I just thought that since there is currently work being done on pgadmin 4
and the debugger piece inside of it, it may be a good idea to bring this up
for discussion now.

-Adam