Feature request: add SOAP optimizer support #4680
Description
Feature request
Add SOAP optimizer support (paper: https://arxiv.org/abs/2409.11321). Provide a built-in implementation and a ready-to-use FSDP config with paper-default hyperparameters (e.g., trainer/config/optim/soap.yaml).
Motivation
I want to evaluate SOAP in verl training runs and align with the paper defaults without maintaining local patches.
Your contribution
I can submit a PR that adds the optimizer implementation, config template, docs, and a small unit test.