[recipe] fix: move all collabllm files into recipe directory

[chenhaiq]

What does this PR do?

resolve issue #3606

1. move and register reward manager into custom_reward_function file
2. register agent loop in agent.yaml
3. move collabllm_interation.py into recipe

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(TaskRunner pid=52293) step:3 - global_seqlen/min:56551 - global_seqlen/max:94884 - global_seqlen/minmax_diff:38333 - global_seqlen/balanced_min:72054 -

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[gemini-code-assist]

Code Review

This pull request refactors the codebase by moving all collabllm related files into the recipe directory, which improves the project structure. The changes primarily consist of file movements and path updates. My review identified two critical issues in the moved code. First, a custom JSON parser is being used, which is risky and hard to maintain; I've suggested replacing it with Python's standard json library for better robustness and security. Second, there's a potential for an IndexError that could crash the reward calculation process, for which I've provided a fix. Addressing these points will significantly improve the code's quality and stability.

[wuxibin89]

Will this register take effect since it's in recipe?

[chenhaiq]

Yes，from change in https://github.com/volcengine/verl/pull/3706/files#diff-2a8ba9274fff2829dcc676eb0e23dc8e7a77d819ec2a07572f4573082a782d2eR114