Quantum Engine Stream Client

[verult]

Summarize the task
Migrate Quantum Engine circuit execution from using unary RPCs to streams.

Prototype: #5982

Acceptance criteria - when is the task considered done?
When all tasks below are completed:

• Integrate with client-facing API
  • migrate EngineProgram.run_sweep() and EngineJob.result() to streaming Integrate StreamManager with run_sweep() verult/Cirq#17
• ResponseDemux Add ResponseDemux #6190
• StreamManager: normal request and response with no breakages Add StreamManager #6199
• StreamManager: recovery Add StreamManager #6199
• EngineClient.run_job_over_stream() implementation Integrate StreamManager with run_sweep() verult/Cirq#17

Future work:

• migrate EngineProgram.run_batch() and run_calibration() to streaming.
• Address TODOs in StreamManager.

@wcourtney