Make executable able to field RPC requests

[joshc-slac]

the ideal would be that GRPC is just a transport layer and we can now invoke any sequence if the corresponding config file exists.

That requires this function be properly implemented with requisite safeguards:

BEAMS/beams/sequencer/Sequencer.py

Line 34 in 0460058

job = GenerateTreeFromRequest(request)

Was previously called "replumb with GRPC" which is correct and needed to make executable, but changed the title so we don't get lost in the weeds and see what the utility of that fancy word is.

Josh also make a little slide deck on the GRPC decision so people don't fight you on it its so normal