[Feature Dev Track] Enhancing VeRL Integration

Feature request

As VeOmni engine has been integrated in VeRL and would gradually replace the legacy FSDP engine, we need the following features to be validated or developed for smooth transition.

• Validate existing actor profiling pipeline in VeRL is working for VeOmni engine.
• Validate Meta-Init in VeRL for VeOmni engine.
• Support chunked linear cross entropy for PPO to avoid monkey-patch from VeRL side. - after #458 - done in #711
• Support router replay.
• Support LoRA
• Tensor hash for true on-policy RL verification and debugging.

cc @piyifan123 @FoolPlayer @Coach257 @TimYangst

Motivation

As explained

Your contribution

I will work on

• Chunked linear cross entropy for PPO
• Router replay
• Tensor hash

Looking forward to volunteers on them