[1/N] docs(sqsim): propose local scenario simulator

[albertywu]

Summary

RFC for SQSim (a Submitqueue Simulation Tool)

Experience Video

sqsim-demo.mov

Stack

1. @ [1/N] docs(sqsim): propose local scenario simulator #383
2. [2/N] docs(sqsim): define scenario and behavior model #384
3. [3/N] feat(orchestrator): publish request stage progress #385
4. [4/N] feat(sqsim): add scenario DSL and registry #386
5. [5/N] feat(sqsim): add modeled runtime primitives #387
6. [6/N] feat(sqsim): implement external system adapters #388
7. [7/N] feat(sqsim): wire modeled adapters into local stack #389
8. [8/N] feat(sqsim): run scenarios against local stack #390
9. [9/N] feat(sqsim): add interactive scenario view #391
10. [10/N] feat(sqsim): add functional scenario suite #392
11. [11/N] docs(sqsim): add user guide #393

[sbalabanov]

With all the live components, realtime clock and scenarios defined through code, the system is very much close to the e2e test rather than simulator.
In the past, simulator was useful to replay a certain traffic from a production system but at shrunk time intervals, which would require adjustable clock and some components mocked - like a CI/build integration.
Let's discuss a proper designation for the framework.