[reward] feat: split reward loop manager and agent loop manager

[yyDing1]

What does this PR do?

Current Implementation:

1. In the single controller, we first launch the reward loop manager (launch reward models and multiple reward workers)
2. We will judge if we can parallelize the reward computation in the agent loop, resulting in a streaming agent_reward_loop
3. If so, we will pass reward_loop_manager.reward_loop_workers to the agent loop, so that it can directly compute rewards in agent loop

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